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Examination Instructions and Guidelines Referenced Items (246, 247, 248, 249, 250, 251, 252, 253, 254, 255, 256, 257)
(252)                       DEPARTMENT OF COMMERCE
                          Patent and Trademark Office
                         [Docket No.: PTO-P-2010-0055]

                        Examination Guidelines Update:
                        Developments in the Obviousness
                         Inquiry After KSR v. Teleflex

AGENCY: United States Patent and Trademark Office, Commerce.

ACTION: Notice.

SUMMARY: The United States Patent and Trademark Office (USPTO or Office) is
issuing an update (2010 KSR Guidelines Update) to its obviousness
guidelines for its personnel to be used when applying the law of
obviousness under 35 U.S.C. 103. This 2010 KSR Guidelines Update highlights
case law developments on obviousness under 35 U.S.C. 103 since the 2007
decision by the United States Supreme Court (Supreme Court) in KSR Int'l
Co. v. Teleflex Inc. These guidelines are intended to be used by Office
personnel in conjunction with the guidance in the Manual of Patent
Examining Procedure when applying the law of obviousness under 35 U.S.C.
103. Members of the public are invited to provide comments on the 2010 KSR
Guidelines Update. The Office is especially interested in receiving
suggestions of recent decisional law in the field of obviousness that would
have particular value as teaching tools.

DATES: Effective Date: This 2010 KSR Guidelines Update is effective
September 1, 2010.

ADDRESSES: Comments concerning this 2010 KSR Guidelines Update may be sent
by electronic mail message over the Internet addressed to
KSR_Guidance@uspto.gov, or submitted by mail addressed to: Mail Stop
Comments - Patents, Commissioner for Patents, P.O. Box 1450, Alexandria, VA
22313-1450. Although comments may be submitted by mail, the Office prefers
to receive comments via the Internet.

FOR FURTHER INFORMATION CONTACT: Kathleen Kahler Fonda or Pinchus M.
Laufer, Legal Advisors, Office of Patent Legal Administration, Office of
the Associate Commissioner for Patent Examination Policy, by telephone at
(571) 272-7754 or (571) 272-7726; by mail addressed to: Mail Stop Comments
Patents, Commissioner for Patents, P.O. Box 1450, Alexandria, VA
22313-1450; or by facsimile transmission to (571) 273-7754, marked to the
attention of Kathleen Kahler Fonda.

SUPPLEMENTARY INFORMATION:

   1. Introduction. The purpose of this 2010 KSR Guidelines Update is to
remind Office personnel of the principles of obviousness explained by the
Supreme Court in KSR Int'l Co. v. Teleflex Inc., 550 U.S 398 (2007) (KSR),
and to provide additional guidance in view of decisions by the United
States Court of Appeals for the Federal Circuit (Federal Circuit) since
KSR. This body of case law developed over the past three years provides
additional examples that will be useful to Office personnel as well as
practitioners during the examination process. Although every question of
obviousness must be decided on its own facts, these cases begin to clarify
the contours of the obviousness inquiry after KSR, and help to show when a
rejection on this basis is proper and when it is not.

   This 2010 KSR Guidelines Update does not constitute substantive rule
making and hence does not have the force and effect of law. It has been
developed as a matter of internal Office management and is not intended to
create any right or benefit, substantive or procedural, enforceable by any
party against the Office. Rejections will continue to be based upon the
substantive law, and it is these rejections that are appealable.
Consequently, any failure by Office personnel to follow this 2010 KSR
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Guidelines Update is neither appealable nor petitionable.

   After a review of the principles of obviousness and Office policy as
reflected in the Manual of Patent Examining Procedure (MPEP), this 2010 KSR
Guidelines Update addresses a number of issues that arise when Office
personnel consider whether or not a claimed invention is obvious. The
concepts discussed are grounded in Federal Circuit cases, and correlated
with existing Office policy as appropriate. A number of cases which have
been selected for their instructional value on the issue of obviousness
will be discussed in detail.

   The law of obviousness will continue to be refined, and Office personnel
are encouraged to maintain an awareness of precedential case law from the
Federal Circuit and precedential decisions of the Board of Patent Appeals
and Interferences (Board) in this area. The Office will train Office
personnel and update the MPEP as necessary to reflect the current state of
the law.

   2. Principles of Obviousness and the Guidelines. In response to the
Supreme Court's April 2007 decision in KSR, the Office developed guidelines
for patent examiners to follow when determining obviousness of a claimed
invention and published these guidelines in the Federal Register and
Official Gazette. See Examination Guidelines for Determining Obviousness
Under 35 U.S.C. 103 in View of the Supreme Court Decision in KSR
International Co. v. Teleflex Inc., 72 FR 57526 (Oct. 10, 2007), 1324 Off.
Gaz. Pat. Office 23 (Nov. 6, 2007) (2007 KSR Guidelines). The 2007 KSR
Guidelines have been incorporated in the MPEP. See MPEP Sec.  2141 (8th ed.
2001) (Rev. 6, Sept. 2007). The purpose of the 2007 KSR Guidelines was to
give Office personnel practical guidance on how to evaluate obviousness
issues under 35 U.S.C. 103(a) in accordance with the Supreme Court's
instruction in KSR. The 2007 KSR Guidelines also alerted Office personnel
to the importance of considering rebuttal evidence submitted by patent
applicants in response to obviousness rejections.

   The 2007 KSR Guidelines pointed out, as had the Supreme Court in KSR,
that the factual inquiries announced in Graham v. John Deere, 383 U.S. 1,
17-18 (1966) (scope and content of the prior art; differences between the
claimed invention and the prior art; level of ordinary skill in the art;
and secondary indicia of nonobviousness), remain the foundation of any
determination of obviousness. It remains true that "[t]he determination of
obviousness is dependent on the facts of each case." Sanofi-Synthelabo v.
Apotex, Inc., 550 F.3d 1075, 1089 (Fed. Cir. 2008) (citing Graham, 383 U.S.
at 17-18 (1966)). As for the reasoning required to support an obviousness
determination, the 2007 KSR Guidelines noted that the teaching-suggestion-
motivation (TSM) test was but one possible approach. The 2007 KSR
Guidelines identified six other rationales gleaned from the KSR decision as
examples of appropriate lines of reasoning that could also be used. The six
other rationales identified in the 2007 KSR Guidelines are: (1) Combining
prior art elements according to known methods to yield predictable results;
(2) simple substitution of one known element for another to obtain
predictable results; (3) use of a known technique to improve similar
devices, methods, or products in the same way; (4) applying a known
technique to a known device, method, or product ready for improvement to
yield predictable results; (5) obvious to try - choosing from a finite
number of identified, predictable solutions, with a reasonable expectation
of success; and (6) known work in one field of endeavor may prompt
variations of it for use in either the same field or a different one based
on design incentives or other market forces if the variations are
predictable to one of ordinary skill in the art. Any rationale employed
must provide a link between the factual findings and the legal conclusion
of obviousness.

   It is important for Office personnel to recognize that when they do
choose to formulate an obviousness rejection using one of the rationales
suggested by the Supreme Court in KSR and discussed in the 2007 KSR
Guidelines, they are to adhere to the instructions provided in the MPEP
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regarding the necessary factual findings. However, the 2007 KSR Guidelines
also stressed that while the Graham inquiries and the associated reasoning
are crucial to a proper obviousness determination, the Supreme Court in KSR
did not place any limit on the particular approach to be taken to formulate
the line of reasoning. In other words, the KSR decision is not to be seen
as replacing a single test for obviousness - the TSM test - with the seven
rationales listed in the 2007 KSR Guidelines. See MPEP §§ 2141 and 2143
(8th ed. 2001) (Rev. 8, July 2010) (references to the MPEP are to Revision
8 of the 8th Edition of the MPEP unless otherwise indicated). It remains
Office policy that appropriate factual findings are required in order to
apply the enumerated rationales properly. If a rejection has been made that
omits one of the required factual findings, and in response to the
rejection a practitioner or inventor points out the omission, Office
personnel must either withdraw the rejection, or repeat the rejection
including all required factual findings.

   3. The Impact of the KSR Decision. KSR's renewed emphasis on the
foundational principles of Graham coupled with its abrogation of the strict
TSM test have clearly impacted the manner in which Office personnel and
practitioners carry out the business of prosecuting patent applications
with regard to issues of obviousness. However, Office personnel as well as
practitioners should also recognize the significant extent to which the
obviousness inquiry has remained constant in the aftermath of KSR.

   In footnote 2 of the 2007 KSR Guidelines, the Office acknowledged that
ongoing developments in the law of obviousness were to be expected in the
wake of the KSR decision. That footnote also stated that it was "not clear
which Federal Circuit decisions will retain their viability" after KSR. See
2007 KSR Guidelines, 72 FR at 57,528 n.2. The edition of the MPEP that was
current when the KSR decision was handed down had made the following
statement in § 2144:

   The rationale to modify or combine the prior art does not have to be
expressly stated in the prior art; the rationale may be expressly or
impliedly contained in the prior art or it may be reasoned from knowledge
generally available to one of ordinary skill in the art, established
scientific principles, or legal precedent established by prior case law.

   MPEP § 2144 (8th ed. 2001) (Rev. 5, Aug. 2006) (citing five pre-KSR
Federal Circuit opinions and two decisions of the Board). The KSR decision
has reinforced those earlier decisions that validated a more flexible
approach to providing reasons for obviousness. However, the Supreme Court's
pronouncement in KSR has at the same time clearly undermined the continued
viability of cases such as In re Lee, 277 F.3d 1338 (Fed. Cir. 2002),
insofar as Lee appears to require a strict basis in record evidence as a
reason to modify the prior art.

   The Supreme Court's flexible approach to the obviousness inquiry is
reflected in numerous pre-KSR decisions, as can be seen in a review of MPEP
§ 2144. This section provides many lines of reasoning to support a
determination of obviousness based upon earlier legal precedent that had
condoned the use of particular examples of what may be considered common
sense or ordinary routine practice (e.g., making integral, changes in
shape, making adjustable). Thus, the type of reasoning sanctioned by the
opinion in KSR has long been a part of the patent examination process. See
MPEP § 2144.

   Although the KSR approach is flexible with regard to the line of
reasoning to be applied, the 2007 KSR Guidelines and MPEP § 2143 state:
"The Supreme Court in KSR noted that the analysis supporting a rejection
under 35 U.S.C. 103 should be made explicit." MPEP § 2143. In Ball Aerosol
v. Limited Brands, 555 F.3d 984 (Fed. Cir. 2009), the Federal Circuit
offered additional instruction as to the need for an explicit analysis. The
Federal Circuit explained, as is consistent with the 2007 KSR Guidelines,
that the Supreme Court's requirement for an explicit analysis does not
require record evidence of an explicit teaching of a motivation to combine
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in the prior art.

   [T]he analysis that "should be made explicit" refers not to the
teachings in the prior art of a motivation to combine, but to the court's
analysis * * *. Under the flexible inquiry set forth by the Supreme Court,
the district court therefore erred by failing to take account of "the
inferences and creative steps," or even routine steps, that an inventor
would employ and by failing to find a motivation to combine related pieces
from the prior art.

   Ball Aerosol, 555 F.3d at 993. The Federal Circuit's directive in Ball
Aerosol was addressed to a lower court, but it applies to Office personnel
as well. When setting forth a rejection, Office personnel are to continue
to make appropriate findings of fact as explained in MPEP §§ 2141 and 2143,
and must provide a reasoned explanation as to why the invention as claimed
would have been obvious to a person of ordinary skill in the art at the
time of the invention. This requirement for explanation remains even in
situations in which Office personnel may properly rely on intangible
realities such as common sense and ordinary ingenuity.

   When considering obviousness, Office personnel are cautioned against
treating any line of reasoning as a per se rule. MPEP § 2144 discusses
supporting a rejection under 35 U.S.C. 103 by reliance on scientific theory
and legal precedent. In keeping with the flexible approach and the
requirement for explanation, Office personnel may invoke legal precedent as
a source of supporting rationale when warranted and appropriately
supported. See MPEP § 2144.04. So, for example, automating a manual
activity, making portable, making separable, reversal or duplication of
parts, or purifying an old product may form the basis of a rejection.
However, such rationales should not be treated as per se rules, but rather
must be explained and shown to apply to the facts at hand. A similar caveat
applies to any obviousness analysis. Simply stating the principle (e.g.,
"art recognized equivalent," "structural similarity") without providing
an explanation of its applicability to the facts of the case at hand is
generally not sufficient to establish a prima facie case of obviousness.

   Many basic approaches that a practitioner may use to demonstrate
nonobviousness also continue to apply in the post-KSR era. Since it is now
clear that a strict TSM approach is not the only way to establish a prima
facie case of obviousness, it is true that practitioners have been required
to shift the emphasis of their nonobviousness arguments to a certain
degree. However, familiar lines of argument still apply, including teaching
away from the claimed invention by the prior art, lack of a reasonable
expectation of success, and unexpected results. Indeed, they may have even
taken on added importance in view of the recognition in KSR of a variety of
possible rationales.

   At the time the KSR decision was handed down, some observers questioned
whether the principles discussed were intended by the Supreme Court to
apply to all fields of inventive endeavor. Arguments were made that because
the technology at issue in KSR involved the relatively well-developed and
predictable field of vehicle pedal assemblies, the decision was relevant
only to such fields. The Federal Circuit has soundly repudiated such a
notion, stating that KSR applies across technologies:

   This court also declines to cabin KSR to the "predictable arts" (as
opposed to the "unpredictable art" of biotechnology). In fact, this record
shows that one of skill in this advanced art would find these claimed
"results" profoundly "predictable."

   In re Kubin, 561 F.3d 1351, 1360 (Fed. Cir. 2009). Thus, Office
personnel should not withdraw any rejection solely on the basis that the
invention lies in a technological area ordinarily considered to be
unpredictable.

   The decisions of the Federal Circuit discussed in this 2010 KSR
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Guidelines Update provide Office personnel as well as practitioners with
additional examples of the law of obviousness. The purpose of the 2007 KSR
Guidelines was, as stated above, to help Office personnel to determine when
a claimed invention is not obvious, and to provide an appropriate
supporting rationale when an obviousness rejection is appropriate. Now that
a body of case law is available to guide Office personnel and practitioners
as to the boundaries between obviousness and nonobviousness, it is possible
in this 2010 KSR Guidelines Update to contrast situations in which the
subject matter was found to have been obvious with those in which it was
determined not to have been obvious. Thus, Office personnel may use this
2010 KSR Guidelines Update in conjunction with the 2007 KSR Guidelines
(incorporated into MPEP §§ 2141 and 2143) to provide a more complete view
of the state of the law of obviousness.

   This 2010 KSR Guidelines Update provides a "teaching point" for each
discussed case. The "teaching point" may be used to quickly determine the
relevance of the discussed case, but should not be used as a substitute for
reading the remainder of the discussion of the case in this 2010 KSR
Guidelines Update. Nor should any case in this 2010 KSR Guidelines Update
be applied or cited in an Office action solely on the basis of what is
stated in the "teaching point" for the case.

   4. Obviousness Examples from Federal Circuit Cases. The impact of the
Supreme Court's decision in KSR can be more readily understood in the
context of factual scenarios. The cases in this 2010 KSR Guidelines Update
are broadly grouped according to obviousness concepts in order to provide
persons involved with patent prosecution with ready access to the examples
that are most pertinent to the issue at hand. The first three groups
correspond directly with three of the rationales identified in the 2007 KSR
Guidelines. These rationales - combining prior art elements, substituting
one known element for another, and obvious to try - have each been the
subject of a significant number of post-KSR obviousness decisions. The
fourth group focuses on issues concerning consideration of evidence during
prosecution. Office personnel as well as practitioners are reminded of the
technology-specific obviousness examples previously posted on the Office's
Web site at http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=
leavingFR.html&log=linklog&to=http://www.uspto.gov/web/offices/pac/dapp/
opla/ksr/ksr_training_materials.htm.

   Although the other rationales discussed in the 2007 KSR Guidelines are
not the focus of separate discussions in this 2010 KSR Guidelines Update,
it will be noted that obviousness concepts such as applying known
techniques, design choice, and market forces are addressed when they arise
in the selected cases. The cases included in this 2010 KSR Guidelines
Update reinforce the idea, presented in the 2007 KSR Guidelines, that there
may be more than one line of reasoning that can properly be applied to a
particular factual scenario. The selected decisions also illustrate the
overlapping nature of the lines of reasoning that may be employed to
establish a prima facie case of obviousness. Although the 2007 KSR
Guidelines presented the rationales as discrete, self-contained lines of
reasoning, and they may indeed be employed that way, it is useful to
recognize that real-world situations may require analyses that may not be
so readily pigeon-holed into distinct categories.

   A. Combining Prior Art Elements. In discussing the obviousness rationale
concerning combining prior art elements, identified as Rationale A, the
2007 KSR Guidelines quoted KSR and noted that "it can be important to
identify a reason that would have prompted a person of ordinary skill in
the relevant field to combine the elements in the way the claimed new
invention does." KSR, 550 U.S. at 401. In view of the cases decided since
KSR, one situation when it is important to identify a reason to combine
known elements in a known manner to obtain predictable results is when the
combination requires a greater expenditure of time, effort, or resources
than the prior art teachings. Even though the components are known, the
combining step is technically feasible, and the result is predictable, the
claimed invention may nevertheless be nonobvious when the combining step
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involves such additional effort that no one of ordinary skill would have
undertaken it without a recognized reason to do so. When a combination
invention involves additional complexity as compared with the prior art,
the invention may be nonobvious unless an examiner can articulate a reason
for including the added features or steps. This is so even when the claimed
invention could have been readily implemented.

   Example 4.1. In re Omeprazole Patent Litigation, 536 F.3d 1361 (Fed.
Cir. 2008). Teaching point: Even where a general method that could have
been applied to make the claimed product was known and within the level of
skill of the ordinary artisan, the claim may nevertheless be nonobvious if
the problem which had suggested use of the method had been previously
unknown.

   The case of In re Omeprazole Patent Litigation is one in which the
claims in question were found to be nonobvious in the context of an
argument to combine prior art elements. The invention involved applying
enteric coatings to a drug in pill form for the purpose of ensuring that
the drug did not disintegrate before reaching its intended site of action.
The drug at issue was omeprazole, the generic name for gastric acid
inhibitor marketed as Prilosec[reg]. The claimed formulation included two
layers of coatings over the active ingredient.

   The district court found that Astra's patent in suit was infringed by
defendants Apotex and Impax. The district court rejected Apotex's defense
that the patents were invalid for obviousness. Apotex had argued that the
claimed invention was obvious because coated omeprazole tablets were known
from a prior art reference, and because secondary subcoatings in
pharmaceutical preparations generally were also known. There was no
evidence of unpredictability associated with applying two different enteric
coatings to omeprazole. However, Astra's reason for applying an intervening
subcoating between the prior art coating and omeprazole had been that the
prior art coating was actually interacting with omeprazole, thereby
contributing to undesirable degradation of the active ingredient. This
degradation of omeprazole by interaction with the prior art coating had not
been recognized in the prior art. Therefore, the district court reasoned
that based on the evidence available, a person of ordinary skill in the art
would have had no reason to include a subcoating in an omeprazole pill
formulation.

   The Federal Circuit affirmed the district court's decision that the
claimed invention was not obvious. Even though subcoatings for enteric drug
formulation were known, and there was no evidence of undue technical
hurdles or lack of a reasonable expectation of success, the formulation was
nevertheless not obvious because the flaws in the prior art formulation
that had prompted the modification had not been recognized. Thus there
would have been no reason to modify the initial formulation, even though
the modification could have been done. Moreover, a person of skill in the
art likely would have chosen a different modification even if he or she had
recognized the problem.

   Office personnel should note that in this case the modification of the
prior art that had been presented as an argument for obviousness was an
extra process step that added an additional component to a known,
successfully marketed formulation. The proposed modification thus amounted
to extra work and greater expense for no apparent reason. This is not the
same as combining known prior art elements A and B when each would have
been expected to contribute its own known properties to the final product.
In the Omeprazole case, in view of the expectations of those of ordinary
skill in the art, adding the subcoating would not have been expected to
confer any particular desirable property on the final product. Rather, the
final product obtained according to the proposed modifications would merely
have been expected to have the same functional properties as the prior art
product.

   The Omeprazole case can also be analyzed in view of the discovery of a
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previously unknown problem by the patentee. If the adverse interaction
between active agent and coating had been known, it might well have been
obvious to use a subcoating. However, since the problem had not been
previously known, there would have been no reason to incur additional time
and expense to add another layer, even though the addition would have been
technologically possible. This is true because the prior art of record
failed to mention any stability problem, despite the acknowledgment during
testimony at trial that there was a known theoretical reason that
omeprazole might be subject to degradation in the presence of the known
coating material.

   Example 4.2. Crocs, Inc. v. U.S. International Trade Commission, 598
F.3d 1294 (Fed. Cir. 2010). Teaching point: A claimed combination of prior
art elements may be nonobvious where the prior art teaches away from the
claimed combination and the combination yields more than predictable
results.

   The case of Crocs, Inc. v. U.S. International Trade Commission is a
decision in which the claimed foam footwear was held by the Federal Circuit
to be nonobvious over a combination of prior art references.

   The claims involved in the obviousness issue were from Crocs' U.S.
Patent No. 6,993,858, and were drawn to footwear in which a one-piece
molded foam base section formed the top of the shoe (the upper) and the
sole. A strap also made of foam was attached to the foot opening of the
upper, such that the strap could provide support to the Achilles portion of
the wearer's foot. The strap was attached via connectors that allowed it to
be in contact with the base section, and to pivot relative to the base
section. Because both the base portion and the strap were made of foam,
friction between the strap and the base section allowed the strap to
maintain its position after pivoting. In other words, the foam strap did
not fall under the force of gravity to a position adjacent to the heel of
the base section.

   The International Trade Commission (ITC) determined that the claims
were obvious over the combination of two pieces of prior art. The first
was the Aqua Clog, which was a shoe that corresponded to the base section
of the footwear of the `858' patent. The second was the Aguerre patent,
which taught heel straps made of elastic or another flexible material. In
the ITC's view, the claimed invention was obvious because the prior art
Aqua Clog differed from the claimed invention only as to the presence of
the strap, and a suitable strap was taught by Aguerre.

   The Federal Circuit disagreed. The Federal Circuit stated that the prior
art did not teach foam heel straps, or that a foam heel strap should be
placed in contact with a foam base. The Federal Circuit pointed out that
the prior art actually counseled against using foam as a material for the
heel strap of a shoe.

   The record shows that the prior art would actually discourage and teach
away from the use of foam straps. An ordinary artisan in this field would
not add a foam strap to the foam Aqua Clog because foam was likely to
stretch and deform, in addition to causing discomfort for a wearer. The
prior art depicts foam as unsuitable for straps.

Id. at 1309.

   The Federal Circuit continued, stating that even if - contrary to fact -
the claimed invention had been a combination of elements that were known in
the prior art, the claims still would have been nonobvious. There was
testimony in the record that the loose fit of the heel strap made the shoe
more comfortable for the wearer than prior art shoes in which the heel
strap was constantly in contact with the wearer's foot. In the claimed
footwear, the foam heel strap contacted the wearer's foot only when needed
to help reposition the foot properly in the shoe, thus reducing wearer
discomfort that could arise from constant contact. This desirable feature
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was a result of the friction between the base section and the strap that
kept the strap in place behind the Achilles portion of the wearer's foot.
The Federal Circuit pointed out that this combination "yielded more than
predictable results." Id. at 1310. Aguerre had taught that friction between
the base section and the strap was a problem rather than an advantage, and
had suggested the use of nylon washers to reduce friction. Thus the Federal
Circuit stated that even if all elements of the claimed invention had been
taught by the prior art, the claims would not have been obvious because the
combination yielded more than predictable results.

   The Federal Circuit's discussion in Crocs serves as a reminder to Office
personnel that merely pointing to the presence of all claim elements in the
prior art is not a complete statement of a rejection for obviousness. In
accordance with MPEP § 2143 A(3), a proper rejection based on the rationale
that the claimed invention is a combination of prior art elements also
includes a finding that results flowing from the combination would have
been predictable to a person of ordinary skill in the art. MPEP § 2143
A(3). If results would not have been predictable, Office personnel should
not enter an obviousness rejection using the combination of prior art
elements rationale, and should withdraw such a rejection if it has been
made.

   Example 4.3. Sundance, Inc. v. DeMonte Fabricating Ltd., 550 F.3d 1356
(Fed. Cir. 2008). Teaching point: A claimed invention is likely to be
obvious if it is a combination of known prior art elements that would
reasonably have been expected to maintain their respective properties or
functions after they have been combined.

   Sundance involved a segmented and mechanized cover for trucks, swimming
pools, or other structures. The claim was found to be obvious over the
prior art applied.

   A first prior art reference taught that a reason for making a segmented
cover was ease of repair, in that a single damaged segment could be readily
removed and replaced when necessary. A second prior art reference taught
the advantages of a mechanized cover for ease of opening. The Federal
Circuit noted that the segmentation aspect of the first reference and the
mechanization function of the second perform in the same way after
combination as they had before. The Federal Circuit further observed that a
person of ordinary skill in the art would have expected that adding
replaceable segments as taught by the first reference to the mechanized
cover of the other would result in a cover that maintained the advantageous
properties of both of the prior art covers.

   Thus, the Sundance case points out that a hallmark of a proper
obviousness rejection based on combining known prior art elements is that
one of ordinary skill in the art would reasonably have expected the
elements to maintain their respective properties or functions after they
have been combined.

   Example 4.4. Ecolab, Inc. v. FMC Corp., 569 F.3d 1335 (Fed Cir. 2009).
Teaching point: A combination of known elements would have been prima facie
obvious if an ordinarily skilled artisan would have recognized an apparent
reason to combine those elements and would have known how to do so.

   In the case of Ecolab, Inc. v. FMC Corp., an "apparent reason to
combine" in conjunction with the technical ability to optimize led to the
conclusion that the claimed invention would have been obvious.

   The invention in question was a method of treating meat to reduce the
incidence of pathogens, by spraying the meat with an antibacterial solution
under specified conditions. The parties did not dispute that a single prior
art reference had taught all of the elements of the claimed invention,
except for the pressure limitation of "at least 50 psi."

   FMC had argued at the district court that the claimed invention would
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have been obvious in view of the first prior art reference mentioned above
in view of a second reference that had taught the advantages of spray-
treating at pressures of 20 to 150 psi when treating meat with a different
antibacterial agent. The district court did not find FMC's argument to be
convincing, and denied the motion for judgment as a matter of law that the
claim was obvious.

   Disagreeing with the district court, the Federal Circuit stated that
"there was an apparent reason to combine these known elements - namely to
increase contact between the [antibacterial solution] and the bacteria on
the meat surface and to use the pressure to wash additional bacteria off
the meat surface." Id. at 1350. The Federal Circuit explained that because
the second reference had taught "using high pressure to improve the
effectiveness of an antimicrobial solution when sprayed onto meat, and
because an ordinarily skilled artisan would have recognized the reasons for
applying [the claimed antibacterial solution] using high pressure and would
have known how to do so, Ecolab's claims combining high pressure with other
limitations disclosed in FMC's patent are invalid as obvious." Id.

   When considering the question of obviousness, Office personnel should
keep in mind the capabilities of a person of ordinary skill. In Ecolab, the
Federal Circuit stated:

   Ecolab's expert admitted that one skilled in the art would know how to
adjust application parameters to determine the optimum parameters for a
particular solution. The question then is whether it would have been
obvious to combine the high pressure parameter disclosed in the Bender
patent with the PAA methods disclosed in FMC's `676 patent. The answer is
yes.

Id. If optimization of the application parameters had not been within the
level of ordinary skill in the art, the outcome of the Ecolab case may well
have been different.

   Example 4.5. Wyers v. Master Lock Co., No. 2009-1412,  - F.3d - , 2010 WL
2901839 (Fed. Cir. July 22, 2010). Teaching point: The scope of analogous
art is to be construed broadly and includes references that are reasonably
pertinent to the problem that the inventor was trying to solve. Common
sense may be used to support a legal conclusion of obviousness so long as
it is explained with sufficient reasoning.

   In the case of Wyers v. Master Lock Co., the Federal Circuit held that
the claimed barbell-shaped hitch pin locks used to secure trailers to
vehicles were obvious.

   The court discussed two different sets of claims in Wyers, both drawn to
improvements over the prior art hitch pin locks. The first improvement was
a removable sleeve that could be placed over the shank of the hitch pin
lock so that the same lock could be used with towing apertures of varying
sizes. The second improvement was an external flat flange seal adapted to
protect the internal lock mechanism from contaminants. Wyers had admitted
that each of several prior art references taught every element of the
claimed inventions except for the removable sleeve and the external
covering. Master Lock had argued that these references, in combination with
additional references teaching the missing elements, would have rendered
the claims obvious.

   The court first addressed the question of whether the additional
references relied on by Master Lock were analogous prior art. As to the
reference teaching the sleeve improvement, the court concluded that it
dealt specifically with using a vehicle to tow a trailer, and was
therefore in the same field of endeavor as Wyers' sleeve improvement. The
reference teaching the sealing improvement dealt with a padlock rather than
a lock for a tow hitch. The court noted that Wyers' specification had
characterized the claimed invention as being in the field of locking
devices, thus at least suggesting that the sealed padlock reference was in
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the same field of endeavor. However, the court also observed that even if
sealed padlocks were not in the same field of endeavor, they were
nevertheless reasonably pertinent to the problem of avoiding contamination
of a locking mechanism for tow hitches. The court explained that the
Supreme Court's decision in KSR "directs [it] to construe the scope of
analogous art broadly." Wyers, slip. op. at 12. For these reasons, the
court found that Master Lock's asserted references were analogous prior
art, and therefore relevant to the obviousness inquiry.

   The court then turned to the question of whether there would have been
adequate motivation to combine the prior art elements as had been urged by
Master Lock. The court recalled the Graham inquiries, and also emphasized
the "expansive and flexible" post-KSR approach to obviousness that must not
"deny factfinders recourse to common sense." Wyers, slip op. at 13 (quoting
KSR, 550 U.S. at 415 and 421). The court stated:

   KSR and our later cases establish that the legal determination of
obviousness may include recourse to logic, judgment, and common sense, in
lieu of expert testimony * * *.

   Thus, in appropriate cases, the ultimate inference as to the existence
of a motivation to combine references may boil down to a question of
"common sense," appropriate for resolution on summary judgment or JMOL.

Id. at 15 (citing Perfect Web Techs., Inc. v. InfoUSA, Inc., 587 F.3d 1324,
1329 (Fed. Cir. 2009); Ball Aerosol, 555 F.3d at 993).

   After reviewing these principles, the court proceeded to explain why
adequate motivation to combine had been established in this case. With
regard to the sleeve improvement, it pointed out that the need for
different sizes of hitch pins was well known in the art, and that this was
a known source of inconvenience and expense for users. The court also
mentioned the marketplace aspect of the issue, noting that space on store
shelves was at a premium, and that removable sleeves addressed this
economic concern. As to the sealing improvement, the court pointed out that
both internal and external seals were well-known means to protect locks
from contaminants. The court concluded that the constituent elements were
being employed in accordance with their recognized functions, and would
have predictably retained their respective functions when combined as
suggested by Master Lock. The court cited In re O'Farrell, 853 F.2d 894,
904 (Fed. Cir. 1988) for the proposition that a reasonable expectation of
success is a requirement for a proper determination of obviousness.

   Office personnel should note that although the Federal Circuit invoked
the idea of common sense in support of a conclusion of obviousness, it did
not end its explanation there. Rather, the court explained why a person of
ordinary skill in the art at the time of the invention, in view of the
facts relevant to the case, would have found the claimed inventions to have
been obvious. As stated in the MPEP:

   The key to supporting any rejection under 35 U.S.C. 103 is the clear
articulation of the reason(s) why the claimed invention would have been
obvious. The Supreme Court in KSR noted that the analysis supporting a
rejection under 35 U.S.C. 103 should be made explicit. The Court quoting In
re Kahn, 441 F.3d 977, 988, 78 USPQ2d 1329, 1336 (Fed. Cir. 2006), stated
that "[R]ejections on obviousness cannot be sustained by mere conclusory
statements; instead, there must be some articulated reasoning with some
rational underpinning to support the legal conclusion of obviousness."

MPEP § 2141 III. Office personnel should continue to provide a reasoned
explanation for every obviousness rejection.

   Example 4.6. DePuy Spine, Inc. v. Medtronic Sofamor Danek, Inc., 567
F.3d 1314 (Fed. Cir. 2009). Teaching point: Predictability as discussed in
KSR encompasses the expectation that prior art elements are capable of
being combined, as well as the expectation that the combination would have
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worked for its intended purpose. An inference that a claimed combination
would not have been obvious is especially strong where the prior art's
teachings undermine the very reason being proffered as to why a person of
ordinary skill would have combined the known elements.

   The claim in DePuy Spine was directed to a polyaxial pedicle screw used
in spinal surgeries that included a compression member for pressing a screw
head against a receiver member. A prior art reference (Puno) disclosed all
of the elements of the claim except for the compression member. Instead,
the screw head in Puno was separated from the receiver member to achieve a
shock absorber effect, allowing some motion between receiver member and the
vertebrae. The missing compression member was readily found in another
prior art reference (Anderson), which disclosed an external fracture
immobilization splint for immobilizing long bones with a swivel clamp
capable of polyaxial movement until rigidly secured by a compression
member. It was asserted during trial that a person of ordinary skill would
have recognized that the addition of Anderson's compression member to
Puno's device would have achieved a rigidly locked polyaxial pedicle screw
covered by the claim.

   In conducting its analysis, the Federal Circuit noted that the
"predictable result" discussed in KSR refers not only to the expectation
that prior art elements are capable of being physically combined, but also
that the combination would have worked for its intended purpose. In this
case, it was successfully argued that Puno "teaches away" from a rigid
screw because Puno warned that rigidity increases the likelihood that the
screw will fail within the human body, rendering the device inoperative for
its intended purpose. In fact, the reference did not merely express a
general preference for pedicle screws having a "shock absorber" effect, but
rather expressed concern for failure and stated that the shock absorber
feature "decrease[s] the chance of failure of the screw of the bone-screw
interface" because "it prevent[s] direct transfer of load from the rod to
the bone-screw interface." Thus, the alleged reason to combine the prior
art elements of Puno and Anderson - increasing the rigidity of the screw -
ran contrary to the prior art that taught that increasing rigidity would
result in a greater likelihood of failure. In view of this teaching and the
backdrop of collective teachings of the prior art, the Federal Circuit
determined that Puno teaches away from the proposed combination such that a
person of ordinary skill would have been deterred from combining the
references as proposed. Secondary considerations evaluated by the Federal
Circuit relating to failure by others and copying also supported the view
that the combination would not have been obvious at the time of the
invention.

   B. Substituting One Known Element for Another. As explained in the 2007
KSR Guidelines, the substitution rationale applies when the claimed
invention can be viewed as resulting from substituting a known element for
an element of a prior art invention. The rationale applies when one of
ordinary skill in the art would have been technologically capable of making
the substitution, and the result obtained would have been predictable. See
MPEP § 2143(B).

   Example 4.7. In re ICON Health & Fitness, Inc., 496 F.3d 1374 (Fed. Cir.
2007). Teaching point: When determining whether a reference in a different
field of endeavor may be used to support a case of obviousness (i.e., is
analogous), it is necessary to consider the problem to be solved.

   The claimed invention in ICON was directed to a treadmill with a folding
tread base that swivels into an upright storage position, including a gas
spring connected between the tread base and the upright structure to assist
in stably retaining the tread base in the storage position. On
reexamination, the examiner rejected the claims as obvious based on a
combination of references including an advertisement (Damark) for a folding
treadmill demonstrating all of the claim elements other than the gas
spring, and a patent (Teague) with a gas spring. Teague was directed to a
bed that folds into a cabinet using a novel dual-action spring that
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reverses force as the mechanism passes a neutral position, rather than a
single-action spring that would provide a force pushing the bed closed at
all times. The dual-action spring reduced the force required to open the
bed from the closed position, while reducing the force required to lift the
bed from the open position.

   The Federal Circuit addressed the propriety of making the combination
since Teague comes from a different field than the application. Teague was
found to be reasonably pertinent to the problem addressed in the
application because the folding mechanism did not require any particular
focus on treadmills, but rather generally addressed problems of supporting
the weight of such a mechanism and providing a stable resting position.

   Other evidence was considered concerning whether one skilled in the art
would have been led to combine the teachings of Damark and Teague.
Appellant argued that Teague teaches away from the invention because it
directs one skilled in the art not to use single-action springs and does
not satisfy the claim limitations as the dual-action springs would render
the invention inoperable. The Federal Circuit considered the arguments and
found that while Teague at most teaches away from using single-action
springs to decrease the opening force, it actually instructed that single-
action springs provide the result desired by the inventors, which was to
increase the opening force provided by gravity. As to inoperability, the
claims were not limited to single-action springs and were so broad as to
encompass anything that assists in stably retaining the tread base, which
is the function that Teague accomplished. Additionally, the fact that the
counterweight mechanism from Teague used a large spring, which appellant
argued would overpower the treadmill mechanism, ignores the modifications
that one skilled in the art would make to a device borrowed from the prior
art. One skilled in the art would size the components from Teague
appropriately for the application.

   ICON is another useful example for understanding the scope of analogous
art. The art applied concerned retaining mechanisms for folding beds, not
treadmills. When determining whether a reference may properly be applied to
an invention in a different field of endeavor, it is necessary to consider
the problem to be solved. It is certainly possible that a reference may be
drawn in such a way that its usefulness as a teaching is narrowly
restricted. However, in ICON, the "treadmill" concept was too narrow a lens
through which to view the art in light of the prior art teachings
concerning the problem to be solved. The Teague reference was analogous art
because "Teague and the current application both address the need to stably
retain a folding mechanism," id. at 1378, and because "nothing about ICON's
folding mechanism requires any particular focus on treadmills," id. at
1380.

   ICON is also informative as to the relationship between the problem to
be solved and existence of a reason to combine. "Indeed, while perhaps not
dispositive of the issue, the finding that Teague, by addressing a similar
problem, provides analogous art to ICON's application goes a long way
towards demonstrating a reason to combine the two references. Because
ICON's broad claims read on embodiments addressing that problem as]
described by Teague, the prior art here indicates a reason to incorporate
its teachings." Id. at 1380-81.

   The Federal Circuit's discussion in ICON also makes clear that if the
reference does not teach that a combination is undesirable, then it cannot
be said to teach away. An assessment of whether a combination would render
the device inoperable must not "ignore the modifications that one skilled
in the art would make to a device borrowed from the prior art." Id. at
1382.

   Example 4.8. Agrizap, Inc. v. Woodstream Corp., 520 F.3d 1337 (Fed. Cir.
2008). Teaching point: Analogous art is not limited to references in the
field of endeavor of the invention, but also includes references that would
have been recognized by those of ordinary skill in the art as useful for
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applicant's purpose.

   Agrizap involved a stationary pest control device for electrocution of
pests such as rats and gophers, in which the device is set in an area where
the pest is likely to encounter it. The only difference between the claimed
device and the prior art stationary pest control device was that the
claimed device employed a resistive electrical switch, while the prior art
device used a mechanical pressure switch. A resistive electrical switch was
taught in two prior art patents, in the contexts of a hand-held pest
control device and a cattle prod.

   In determining that the claimed invention was obvious, the Federal
Circuit noted that "[t]he asserted claims simply substitute a resistive
electrical switch for the mechanical pressure switch" employed in the prior
art device. Id. at 1344. In this case, the prior art concerning the hand-
held devices revealed that the function of the substituted resistive
electrical switch was well known and predictable, and that it could be used
in a pest control device. According to the Federal Circuit, the references
that taught the hand-held devices showed that "the use of an animal body as
a resistive switch to complete a circuit for the generation of an electric
charge was already well known in the prior art." Id. Finally, the Federal
Circuit noted that the problem solved by using the resistive electrical
switch in the prior art hand-held devices - malfunction of mechanical
switches due to dirt and dampness - also pertained to the prior art
stationary pest control device.

   The Federal Circuit recognized Agrizap as "a textbook case of when the
asserted claims involve a combination of familiar elements according to
known methods that does no more than yield predictable results." Id.
Agrizap exemplifies a strong case of obviousness based on simple
substitution that was not overcome by the objective evidence of
nonobviousness offered. It also demonstrates that analogous art is not
limited to the field of applicant's endeavor, in that one of the references
that used an animal body as a resistive switch to complete a circuit for
the generation of an electric charge was not in the field of pest control.

   Example 4.9. Muniauction, Inc. v. Thomson Corp., 532 F.3d 1318 (Fed.
Cir. 2008). Teaching point: Because Internet and Web browser technologies
had become commonplace for communicating and displaying information, it
would have been obvious to adapt existing processes to incorporate them for
those functions.

   The invention at issue in Muniauction was a method for auctioning
municipal bonds over the Internet. A municipality could offer a package of
bond instruments of varying principal amounts and maturity dates, and an
interested buyer would then submit a bid comprising a price and interest
rate for each maturity date. It was also possible for the interested buyer
to bid on a portion of the offering. The claimed invention considered all
of the noted parameters to determine the best bid. It operated on
conventional Web browsers and allowed participants to monitor the course of
the auction.

   The only difference between the prior art bidding system and the claimed
invention was the use of a conventional Web browser. At trial, the district
court had determined that Muniauction's claims were not obvious. Thomson
argued that the claimed invention amounted to incorporating a Web browser
into a prior art auction system, and was therefore obvious in light of KSR.
Muniauction rebutted the argument by offering evidence of skepticism by
experts, copying, praise, and commercial success. Although the district
court found the evidence to be persuasive of nonobviousness, the Federal
Circuit disagreed. It noted that a nexus between the claimed invention and
the proffered evidence was lacking because the evidence was not coextensive
with the claims at issue. For this reason, the Federal Circuit determined
that Muniauction's evidence of secondary considerations was not entitled to
substantial weight.

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   The Federal Circuit analogized this case to Leapfrog Enterprises, Inc.
v. Fisher-Price, Inc., 485 F.3d 1157 (Fed. Cir. 2007), cited in the 2007
KSR Guidelines. The Leapfrog case involved a determination of obviousness
based on application of modern electronics to a prior art mechanical
children's learning device. In Leapfrog, the court had noted that market
pressures would have prompted a person of ordinary skill to use modern
electronics in the prior art device. Similarly in Muniauction, market
pressures would have prompted a person of ordinary skill to use a
conventional Web browser in a method of auctioning municipal bonds.

   Example 4.10. Aventis Pharma Deutschland v. Lupin Ltd., 499 F.3d 1293
(Fed. Cir. 2007). Teaching point: A chemical compound would have been
obvious over a mixture containing that compound as well as other compounds
where it was known or the skilled artisan had reason to believe that some
desirable property of the mixture was derived in whole or in part from the
claimed compound, and separating the claimed compound from the mixture was
routine in the art.

   In Aventis, the claims were drawn to the 5(S) stereoisomer of the blood
pressure drug ramipril in stereochemically pure form, and to compositions
and methods requiring 5(S) ramipril. The 5(S) stereoisomer is one in which
all five stereocenters in the ramipril molecule are in the S rather than
the R configuration. A mixture of various stereoisomers including 5(S)
ramipril had been taught by the prior art. The question before the court
was whether the purified single stereoisomer would have been obvious over
the known mixture of stereoisomers.

   The record showed that the presence of multiple S stereocenters in drugs
similar to ramipril was known to be associated with enhanced therapeutic
efficacy. For example, when all of the stereocenters were in the S form in
the related drug enalapril (SSS enalapril) as compared with only two
stereocenters in the S form (SSR enalapril), the therapeutic potency was
700 times as great. There was also evidence to indicate that conventional
methods could be used to separate the various stereoisomers of ramipril.

   The district court saw the issue as a close case, because, in its view,
there was no clear motivation in the prior art to isolate 5(S) ramipril.
However, the Federal Circuit disagreed, and found that the claims would
have been obvious. The Federal Circuit cautioned that requiring such a
clearly stated motivation in the prior art to isolate 5(S) ramipril ran
counter to the Supreme Court's decision in KSR. The
court stated:

   Requiring an explicit teaching to purify the 5(S) stereoisomer from a
mixture in which it is the active ingredient is precisely the sort of rigid
application of the TSM test that was criticized in KSR.

   Id. at 1301. The Aventis court also relied on the settled principle that
in chemical cases, structural similarity can provide the necessary reason
to modify prior art teachings. The Federal Circuit also addressed the kind
of teaching that would be sufficient in the absence of an explicitly stated
prior art-based motivation, explaining that an expectation of similar
properties in light of the prior art can be sufficient, even without an
explicit teaching that the compound will have a particular utility.

   In the chemical arts, the cases involving so-called "lead compounds"
form an important subgroup of the obviousness cases that are based on
substitution. The Federal Circuit has had a number of opportunities since
the KSR decision to discuss the circumstances under which it would have
been obvious to modify a known compound to arrive at a claimed compound.
The following cases explore the selection of a lead compound, the need to
provide a reason for any proposed modification, and the predictability of
the result.

   Example 4.11. Eisai Co. Ltd. v. Dr. Reddy's Labs., Ltd., 533 F.3d 1353
(Fed. Cir. 2008). Teaching point: A claimed compound would not have been
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obvious where there was no reason to modify the closest prior art lead
compound to obtain the claimed compound and the prior art taught that
modifying the lead compound would destroy its advantageous property. Any
known compound may serve as a lead compound when there is some reason for
starting with that lead compound and modifying it to obtain the claimed
compound.

   Eisai concerns the pharmaceutical compound rabeprazole. Rabeprazole is a
proton pump inhibitor for treating stomach ulcers and related disorders.
The Federal Circuit affirmed the district court's summary judgment of
nonobviousness, stating that no reason had been advanced to modify the
prior art compound in a way that would destroy an advantageous property.

   Co-defendant Teva based its obviousness argument on the structural
similarity between rabeprazole and lansoprazole. The compounds were
recognized as sharing a common core, and the Federal Circuit characterized
lansoprazole as a "lead compound." The prior art compound lansoprazole was
useful for the same indications as rabeprazole, and differed from
rabeprazole only in that lansoprazole has a trifluoroethoxy substituent at
the 4-position of the pyridine ring, while rabeprazole has a methoxypropoxy
substituent. The trifluoro substituent of lansoprazole was known to be a
beneficial feature because it conferred lipophilicity to the compound. The
ability of a person of ordinary skill to carry out the modification to
introduce the methoxypropoxy substituent, and the predictability of the
result were not addressed.

   Despite the significant similarity between the structures, the Federal
Circuit did not find any sufficient reason to modify the lead compound.
According to the Federal Circuit:

   Obviousness based on structural similarity thus can be proved by
identification of some motivation that would have led one of ordinary skill
in the art to select and then modify a known compound (i.e. a lead
compound) in a particular way to achieve the claimed compound. * * * In
keeping with the flexible nature of the obviousness inquiry, KSR Int'l Co.
v. Teleflex Inc., 550 U.S. 398, 127 S.Ct. 1727, 1739, 167 L.Ed.2d 705
(2007), the requisite motivation can come from any number of sources and
need not necessarily be explicit in the art. See Aventis Pharma Deutschland
GmbH v. Lupin, Ltd., 499 F.3d 1293, 1301 (Fed. Cir. 2007). Rather "it is
sufficient to show that the claimed and prior art compounds possess a
`sufficiently close relationship * * * to create an expectation,' in light
of the totality of the prior art, that the new compound will have `similar
properties' to the old." Id. (quoting Dillon, 919 F.2d at 692).

   Eisai, 533 F.3d at 1357. The prior art taught that introducing a
fluorinated substituent was known to increase lipophilicity, so a skilled
artisan would have expected that replacing the trifluoroethoxy substituent
with a methoxypropoxy substituent would have reduced the lipophilicity of
the compound. Thus, the prior art created the expectation that rabeprazole
would be less useful than lansoprazole as a drug for treating stomach
ulcers and related disorders because the proposed modification would have
destroyed an advantageous property of the prior art compound. The compound
was not obvious as argued by Teva because, upon consideration of all of the
facts of the case, a person of ordinary skill in the art at the time of the
invention would not have had a reason to modify lansoprazole so as to form
rabeprazole.

   Office personnel are cautioned that the term "lead compound" in a
particular opinion can have a contextual meaning that may vary from the way
a pharmaceutical chemist might use the term. In the field of pharmaceutical
chemistry, the term "lead compound" has been defined variously as "a
chemical compound that has pharmacological or biological activity and whose
chemical structure is used as a starting point for chemical modifications
in order to improve potency, selectivity, or pharmacokinetic parameters;"
"[a] compound that exhibits pharmacological properties which suggest its
development;" and "a potential drug being tested for safety and efficacy."
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See, e.g.,http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=
leavingFR.html&log=linklog&to=http://en.wikipedia.org/wiki/Lead_compound,
accessed January 13, 2010; http://frwebgate.access.gpo.gov/cgi-bin/leaving.
cgi?from=leavingFR.html&log=linklog&to=http://www.combichemistry.com/
glossary_k.html, accessed January 13, 2010; and http://frwebgate.access.
gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://www.
building biotechnology.com/glossary4.php,accessed January 13, 2010.

   The Federal Circuit in Eisai makes it clear that from the perspective of
the law of obviousness, any known compound might possibly serve as a lead
compound: "Obviousness based on structural similarity thus can be proved by
identification of some motivation that would have led one of ordinary skill
in the art to select and then modify a known compound (i.e. a lead '
compound) in a particular way to achieve the claimed compound." Eisai, 533
F.3d at 1357. Thus, Office personnel should recognize that a proper
obviousness rejection of a claimed compound that is useful as a drug might
be made beginning with an inactive compound, if, for example, the reasons
for modifying a prior art compound to arrive at the claimed compound have
nothing to do with pharmaceutical activity. The inactive compound would not
be considered to be a lead compound by pharmaceutical chemists, but could
potentially be used as such when considering obviousness. Office personnel
might also base an obviousness rejection on a known compound that
pharmaceutical chemists would not select as a lead compound due to expense,
handling issues, or other business considerations. However, there must be
some reason for starting with that lead compound other than the mere fact
that the "lead compound" merely exists. See Altana Pharma AG v. Teva
Pharmaceuticals USA, Inc., 566 F.3d 999, 1007 (Fed. Cir. 2009) (holding
that there must be some reason "to select and modify a known compound");
Ortho-McNeil Pharmaceutical, Inc. v. Mylan Labs, Inc., 520 F.3d 1358, 1364
(Fed. Cir. 2008).

   Example 4.12. Procter & Gamble Co. v. Teva Pharmaceuticals USA, Inc.,
566 F.3d 989 (Fed. Cir. 2009). Teaching point: It is not necessary to
select a single compound as a "lead compound" in order to support an
obviousness rejection. However, where there was reason to select and modify
the lead compound to obtain the claimed compound, but no reasonable
expectation of success, the claimed compound would not have been obvious.

   A chemical compound was also found to be nonobvious in Procter & Gamble.
The compound at issue was risedronate - the active ingredient of Procter &
Gamble's osteoporosis drug Actonel[reg]. Risedronate is an example of a
bisphosphonate, which is a class of compounds known to inhibit bone
resorption.

   When Procter & Gamble sued Teva for infringement, Teva defended by
arguing invalidity for obviousness over one of Procter & Gamble's earlier
patents. The prior art patent did not teach risedronate, but instead taught
thirty-six other similar compounds including 2-pyr EHDP that were
potentially useful with regard to osteoporosis. Teva argued obviousness on
the basis of structural similarity to 2-pyr EHDP, which is a positional
isomer of risedronate.

   The district court found no reason to select 2-pyr EHDP as a lead
compound in light of the unpredictable nature of the art, and no reason to
modify it so as to obtain risedronate. In addition, there were unexpected
results as to potency and toxicity. Therefore the district court found that
Teva had not made a prima facie case, and even if it had, it was rebutted
by evidence of unexpected results.

   The Federal Circuit affirmed the district court's decision. The Federal
Circuit did not deem it necessary in this case to consider the question of
whether 2-pyr EHDP had been appropriately selected as a lead compound.
Rather, the Federal Circuit stated that if 2-pyr EHDP is presumed to be an
appropriate lead compound, there must be both a reason to modify it so as
to make risedronate, and a reasonable expectation of success. Here there
was no evidence that the necessary modifications would have been routine,
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so there would have been no reasonable expectation of success.

   Procter & Gamble is also informative in its discussion of the treatment
of secondary considerations of non-obviousness. Although the court found
that no prima facie case of obviousness had been presented, it proceeded to
analyze Procter & Gamble's proffered evidence countering the alleged prima
facie case in some detail, thus shedding light on the proper treatment of
such evidence.

   The Federal Circuit noted in dicta that even if a prima facie case of
obviousness had been established, sufficient evidence of unexpected results
was introduced to rebut such a showing. At trial, the witnesses
consistently testified that the properties of risedronate were not
expected, offering evidence that researchers did not predict either the
potency or the low dose at which the compound was effective, and that the
superior properties were unexpected and could not be predicted. Tests
comparing risedronate to a compound in the prior art reference showed that
risedronate outperformed the other compound by a substantial margin, could
be administered in a greater amount without an observable toxic effect, and
was not lethal at the same levels as the other compound. The weight of the
evidence and the credibility of the witnesses were sufficient to show
unexpected results that would have rebutted an obviousness determination.
Thus, nonobviousness can be shown when a claimed invention is shown to have
unexpectedly superior properties when compared to the prior art.

   The court then addressed the evidence of commercial success of
risedronate and the evidence that risedronate met a long-felt need. The
court pointed out that little weight was to be afforded to the commercial
success because the competing product was also assigned to Procter &
Gamble. However, the Federal Circuit affirmed the district court's
conclusion that risedronate met a long-felt, unsatisfied need. The court
rejected Teva's contention that because the competing drug was available
before Actonel[supreg], there was no unmet need that the invention
satisfied. The court emphasized that whether there was a long-felt
unsatisfied need is to be evaluated based on the circumstances as of the
filing date of the challenged invention - not as of the date that the
invention is brought to market.

   It should be noted that the lead compound cases do not stand for the
proposition that identification of a single lead compound is necessary in
every obviousness rejection of a chemical compound. For example, one might
envision a suggestion in the prior art to formulate a compound having
certain structurally defined moieties, or moieties with certain properties.
If a person of ordinary skill would have known how to synthesize such a
compound, and the structural and/or functional result could reasonably have
been predicted, then a prima facie case of obviousness of the claimed
chemical compound might exist even without identification of a particular
lead compound. As a second example, it could be possible to view a claimed
compound as consisting of two known compounds attached via a chemical
linker. The claimed compound might properly be found to have been obvious
if there would have been a reason to link the two, if one of ordinary skill
would have known how to do so, and if the resulting compound would have
been the predictable result of the linkage procedure. Thus, Office
personnel should recognize that in certain situations, it may be proper to
reject a claimed chemical compound as obvious even without identifying a
single lead compound.

   Example 4.13. Altana Pharma AG v. Teva Pharmaceuticals USA, Inc., 566
F.3d 999 (Fed. Cir. 2009). Teaching point: Obviousness of a chemical
compound in view of its structural similarity to a prior art compound may
be shown by identifying some line of reasoning that would have led one of
ordinary skill in the art to select and modify a prior art lead compound in
a particular way to produce the claimed compound. It is not necessary for
the reasoning to be explicitly found in the prior art of record, nor is it
necessary for the prior art to point to only a single lead compound.

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   Although the decision reached by the Federal Circuit in Altana involved
a motion for preliminary injunction and did not include a final
determination of obviousness, the case is nevertheless instructive as to
the issue of selecting a lead compound.

   The technology involved in Altana was the compound pantoprazole, which
is the active ingredient in Altana's antiulcer drug Protonix[supreg].
Pantoprazole belongs to a class of compounds known as proton pump
inhibitors that are used to treat gastric acid disorders
in the stomach.

   Altana accused Teva of infringement. The district court denied Altana's
motion for preliminary injunction for failure to establish a likelihood of
success on the merits, determining that Teva had demonstrated a substantial
question of invalidity for obviousness in light of one of Altana's prior
patents. Altana's patent discussed a compound referred to as compound 12,
which was one of eighteen compounds disclosed. The claimed compound
pantoprazole was structurally similar to compound 12. The district court
found that one of ordinary skill in the art would have selected compound 12
as a lead compound for modification, and the Federal Circuit affirmed.

   Obviousness of a chemical compound in view of its structural similarity
to a prior art compound may be shown by identifying some line of reasoning
that would have led one of ordinary skill in the art to select and modify
the prior art compound in a particular way to produce the claimed compound.
The necessary line of reasoning can be drawn from any number of sources and
need not necessarily be explicitly found in the prior art of record. The
Federal Circuit determined that ample evidence supported the district
court's finding that compound 12 was a natural choice for further
development. For example, Altana's prior art patent claimed that its
compounds, including compound 12, were improvements over the prior art;
compound 12 was disclosed as one of the more potent of the eighteen
compounds disclosed; the patent examiner had considered the compounds of
Altana's prior art patent to be relevant during the prosecution of the
patent in suit; and experts had opined that one of ordinary skill in the
art would have selected the eighteen compounds to pursue further
investigation into their potential as proton pump inhibitors.

   In response to Altana's argument that the prior art must point to only a
single lead compound for further development, the Federal Circuit stated
that a "restrictive view of the lead compound test would present a rigid
test similar to the teaching-suggestion-motivation test that the Supreme
Court explicitly rejected in KSR * * *. The district court in this case
employed a flexible approach - one that was admittedly preliminary - and
found that the defendants had raised a substantial question that one of
skill in the art would have used the more potent compounds of [Altana's
prior art] patent, including compound 12, as a starting point from which to
pursue further development efforts. That finding was not clearly
erroneous." Id. at 1008.

   C. The "Obvious to Try" Rationale. The question of whether a claimed
invention can be shown to be obvious based on an "obvious to try" line of
reasoning has been explored extensively by the Federal Circuit in several
cases since the KSR decision. The 2007 KSR Guidelines explain, in view of
the Supreme Court's instruction, that this rationale is only appropriate
when there is a recognized problem or need in the art; there are a finite
number of identified, predictable solutions to the recognized need or
problem; and one of ordinary skill in the art could have pursued these
known potential solutions with a reasonable expectation of success. The
case law in this area is developing quickly in the chemical arts, although
the rationale has been applied in other art areas as well.

   Some commentators on the KSR decision have expressed a concern that
because inventive activities are always carried out in the context of what
has come before and not in a vacuum, few inventions will survive scrutiny
under an obvious to try standard. The cases decided since KSR have proved
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this fear to have been unfounded. Courts appear to be applying the KSR
requirement for "a finite number of identified predictable solutions" in a
manner that places particular emphasis on predictability and the reasonable
expectations of those of ordinary skill in the art.

   In a recent Federal Circuit decision, the court pointed out the
challenging nature of the task faced by the courts - and likewise by Office
personnel - when considering the viability of an obvious to try argument:
"The evaluation of the choices made by a skilled scientist, when such
choices lead to the desired result, is a challenge to judicial
understanding of how technical advance is achieved in the particular field
of science or technology." Abbott Labs. v. Sandoz, Inc., 544 F.3d 1341,
1352 (Fed. Cir. 2008). The Federal Circuit cautioned that an obviousness
inquiry based on an obvious to try rationale must always be undertaken in
the context of the subject matter in question, "including the
characteristics of the science or technology, its state of advance, the
nature of the known choices, the specificity or generality of the prior
art, and the predictability of results in the area of interest." Id.

   Example 4.14. In re Kubin, 561 F.3d 1351 (Fed. Cir. 2009). Teaching
point: A claimed polynucleotide would have been obvious over the known
protein that it encodes where the skilled artisan would have had a
reasonable expectation of success in deriving the claimed polynucleotide
using standard biochemical techniques, and the skilled artisan would have
had a reason to try to isolate the claimed polynucleotide. KSR applies to
all technologies, rather than just the "predictable" arts.

   The Federal Circuit's decision in In re Kubin was an affirmance of the
Board's decision in Ex parte Kubin, 83 USPQ2d 1410 (Bd. Pat. App. & Interf.
2007), and the Board in turn had affirmed the examiner's determination that
the claims in question would have been obvious over the prior art applied.
A discussion of Ex parte Kubin was included in the 2007 KSR Guidelines. See
2007 KSR Guidelines, 72 FR at 57532. The claimed invention in Kubin was an
isolated nucleic acid molecule. The claim stated that the nucleic acid
encoded a particular polypeptide. The encoded polypeptide was identified in
the claim by its partially specified sequence, and by its ability to bind
to a specified protein. A prior art patent to Valiante taught the
polypeptide encoded by the claimed nucleic acid, but did not disclose
either the sequence of the polypeptide, or the claimed isolated nucleic
acid molecule. However, Valiante did disclose that by employing
conventional methods, such as those disclosed by a prior art laboratory
manual by Sambrook, the sequence of the polypeptide could be determined,
and the nucleic acid molecule could be isolated. In view of Valiante's
disclosure of the polypeptide, and of routine prior art methods for
sequencing the polypeptide and isolating the nucleic acid molecule, the
Board found that a person of ordinary skill in the art would have had a
reasonable expectation that a nucleic acid molecule within the claimed
scope could have been successfully obtained.

   Relying on In re Deuel, 51 F.3d 1552 (Fed. Cir. 1995), Appellant argued
that it was improper for the Office to use the polypeptide of the Valiante
patent together with the methods described in Sambrook to reject a claim
drawn to a specific nucleic acid molecule without providing a reference
showing or suggesting a structurally similar nucleic acid molecule. Citing
KSR, the Board stated that "when there is motivation to solve a problem and
there are a finite number of identified, predictable solutions, a person of
ordinary skill has good reason to pursue the known options within his or
her technical grasp. If this leads to anticipated success, it is likely the
product not of innovation but of ordinary skill and common sense." The
Board noted that the problem facing those in the art was to isolate a
specific nucleic acid, and there were a limited number of methods available
to do so. The Board concluded that the skilled artisan would have had
reason to try these methods with the reasonable expectation that at least
one would be successful. Thus, isolating the specific nucleic acid molecule
claimed was "the product not of innovation but of ordinary skill and common
sense." The Board's reasoning was substantially adopted by the Federal
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Circuit. However, it is important to note that in the Kubin decision, the
Federal Circuit held that "the Supreme Court in KSR unambiguously
discredited" the Federal Circuit's decision in Deuel, insofar as it
"implies the obviousness inquiry cannot consider that the combination of
the claim's constituent elements was `obvious to try.'" Kubin, 561 F.3d at
1358. Instead, Kubin stated that KSR "resurrects" the Federal Circuit's own
wisdom in O'Farrell, in which "to differentiate between proper and improper
applications of `obvious to try,'" the Federal Circuit "outlined two
classes of situations where `obvious to try' is erroneously equated with
obviousness under § 103." Kubin, 561 F.3d at 1359. These two classes of
situations are: (1) When what would have been "obvious to try" would have
been to vary all parameters or try each of numerous possible choices until
one possibly arrived at a successful result, where the prior art gave
either no indication of which parameters were critical or no direction as
to which of many possible choices is likely to be successful; and (2) when
what was "obvious to try" was to explore a new technology or general
approach that seemed to be a promising field of experimentation, where the
prior art gave only general guidance as to the particular form of the
claimed invention or how to achieve it. Id. (citing O'Farrell, 853 F.2d at
903).

   Example 4.15. Takeda Chemical Industries, Ltd. v. Alphapharm Pty., Ltd.,
492 F.3d 1350 (Fed. Cir. 2007). Teaching point: A claimed compound would
not have been obvious where it was not obvious to try to obtain it from a
broad range of compounds, any one of which could have been selected as the
lead compound for further investigation, and the prior art taught away from
using a particular lead compound, and there was no predictability or
reasonable expectation of success in making the particular modifications
necessary to transform the lead compound into the claimed compound.

   Takeda is an example of a chemical case in which the Federal Circuit
found that the claim was not obvious. The claimed compound was
pioglitazone, a member of a class of drugs known as thiazolidinediones
(TZDs) marketed by Takeda as a treatment for Type 2 diabetes. The Takeda
case brings together the concept of a "lead compound" and the obvious-to-
try argument.

   Alphapharm had filed an Abbreviated New Drug Application with the Food
and Drug Administration, which was a technical act of infringement of
Takeda's patent. When Takeda brought suit, Alphapharm's defense was that
Takeda's patent was invalid due to obviousness. Alphapharm argued that a
two-step modification - involving homologation and ring-walking - of a known
compound identified as "compound b" would have produced pioglitazone, and
that it was therefore obvious.

   The district court found that there would have been no reason to select
compound b as a lead compound. There were a large number of similar prior
art TZD compounds; fifty-four were specifically identified in Takeda's
prior patent, and the district court observed that "hundreds of millions"
were more generally disclosed. Although the parties agreed that compound b
represented the closest prior art, one reference had taught certain
disadvantageous properties associated with compound b, which according to
the district court would have taught the skilled artisan not to select that
compound as a lead compound. The district court found no prima facie case
of obviousness, and stated that even if a prima facie case had been
established, it would have been overcome in this case in view of the
unexpected lack of toxicity of pioglitazone.

   The Federal Circuit affirmed the decision of the district court, citing
the need for a reason to modify a prior art compound. The Federal Circuit
quoted KSR, stating:

   The KSR Court recognized that "[w]hen there is a design need or market
pressure to solve a problem and there are a finite number of identified,
predictable solutions, a person of ordinary skill has good reason to pursue
the known options within his or her technical grasp." KSR, 127 S.Ct. at
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1732. In such circumstances, "the fact that a combination was obvious to
try might show that it was obvious under § 103." Id. That is not the case
here. Rather than identify predictable solutions for antidiabetic
treatment, the prior art disclosed a broad selection of compounds any one
of which could have been selected as a lead compound for further
investigation. Significantly, the closest prior art compound (compound b,
the 6-methyl) exhibited negative properties that would have directed one of
ordinary skill in the art away from that compound. Thus, this case fails to
present the type of situation contemplated by the Court when it stated that
an invention may be deemed obvious if it was "obvious to try." The evidence
showed that it was not obvious to try.

   Takeda, 492 F.3d at 1359.
   Accordingly, Office personnel should recognize that the obvious to try
rationale does not apply when the appropriate factual findings cannot be
made. In Takeda, there was a recognized need for treatment of diabetes.
However, there was no finite number of identified, predictable solutions to
the recognized need, and no reasonable expectation of success. There were
numerous known TZD compounds, and although one clearly represented the
closest prior art, its known disadvantages rendered it unsuitable as a
starting point for further research, and taught the skilled artisan away
from its use. Furthermore, even if there had been reason to select compound
b, there had been no predictability or reasonable expectation of success
associated with the particular modifications necessary to transform
compound b into the claimed compound pioglitazone. Thus, an obviousness
rejection based on an obvious to try rationale was not appropriate in this
situation.

   Example 4.16. Ortho-McNeil Pharmaceutical, Inc. v. Mylan Labs, Inc., 520
F.3d 1358 (Fed. Cir. 2008). Teaching point: Where the claimed anti-
convulsant drug had been discovered somewhat serendipitously in the course
of research aimed at finding a new anti-diabetic drug, it would not have
been obvious to try to obtain a claimed compound where the prior art did
not present a finite and easily traversed number of potential starting
compounds, and there was no apparent reason for selecting a particular
starting compound from among a number of unpredictable alternatives.

   The Ortho-McNeil case provides another example in which a chemical
compound was determined not to be obvious. The claimed subject matter was
topiramate, which is used as an anti-convulsant. As in DePuy Spine, whether
the combination would predictably be effective for its intended purpose is
part of the obviousness analysis.

   In the course of working toward a new anti-diabetic drug, Ortho-McNeil's
scientist had unexpectedly discovered that a reaction intermediate had
anti-convulsant properties. Mylan's defense of invalidity due to
obviousness rested on an obvious to try argument. However, Mylan did not
explain why it would have been obvious to begin with an anti-diabetic drug
precursor, especially the specific one that led to topiramate, if one had
been seeking an anti-convulsant drug. The district court ruled on summary
judgment that Ortho-McNeil's patent was not invalid for obviousness.

   The Federal Circuit affirmed. The Federal Circuit pointed out that there
was no apparent reason why a person of ordinary skill would have chosen the
particular starting compound or the particular synthetic pathway that led
to topiramate as an intermediate. Furthermore, there would have been no
reason to test that intermediate for anticonvulsant properties if treating
diabetes had been the goal. The Federal Circuit recognized an element of
serendipity in this case, which runs counter to the requirement for
predictability. Summarizing their conclusion with regard to Mylan's obvious
to try argument, the Federal Circuit stated:

   [T]his invention, contrary to Mylan's characterization, does not present
a finite (and small in the context of the art) number of options easily
traversed to show obviousness * * *. KSR posits a situation with a finite,
and in the context of the art, small or easily traversed, number of options
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that would convince an ordinarily skilled artisan of obviousness* * * .
[T]his clearly is not the easily traversed, small and finite number of
alternatives that KSR suggested might support an inference of obviousness.

   Id. at 1364. Thus, Ortho-McNeil helps to clarify the Supreme Court's
requirement in KSR for "a finite number" of predictable solutions when an
obvious to try rationale is applied: Under the Federal Circuit's case law
"finite" means "small or easily traversed" in the context of the art in
question. As taught in Abbott, discussed above, it is essential that the
inquiry be placed in the context of the subject matter at issue, and each
case must be decided on its own facts.

   Example 4.17. Bayer Schering Pharma A.G. v. Barr Labs., Inc., 575 F.3d
1341 (Fed. Cir. 2009). Teaching point: A claimed compound would have been
obvious where it was obvious to try to obtain it from a finite and easily
traversed number of options that was narrowed down from a larger set of
possibilities by the prior art, and the outcome of obtaining the claimed
compound was reasonably predictable.

   In Bayer the claimed invention was an oral contraceptive containing
micronized drospirenone marketed as Yasmin[reg].

   The prior art compound drospirenone was known to be a poorly water-
soluble, acid-sensitive compound with contraceptive effects. It was also
known in the art that micronization improves the solubility of poorly water
soluble drugs.

   Based on the known acid sensitivity, Bayer had studied how effectively
an enteric-coated drospirenone tablet delivered a formulation as compared
to an intravenous injection of the same formulation to measure the
"absolute bioavailability" of the drug. Bayer added an unprotected (normal)
drospirenone tablet and compared its bioavailability to that of the
enteric-coated formulation and the intravenous delivery. Bayer expected to
find that the enteric-coated tablet would produce a lower bioavailability
than an intravenous injection, while the normal pill would produce an even
lower bioavailability than the enteric-coated tablet. However, they found
that despite observations that drospirenone would quickly isomerize in a
highly acidic environment (supporting the belief that an enteric coating
would be necessary to preserve bioavailability), the normal pill and the
enteric-coated pill resulted in the same bioavailability. Following this
study, Bayer developed micronized drospirenone in a normal pill, the basis
for the disputed patent.

   The district court found that a person having ordinary skill in the art
would have considered the prior art result that a structurally related
compound, spirorenone, though acid-sensitive, would nevertheless absorb in
vivo, would have suggested the same result for drospirenone. It also found
that while another reference taught that drospirenone isomerizes in vitro
when exposed to acid simulating the human stomach, a person of ordinary
skill would have been aware of the study's shortcomings, and would have
verified the findings as suggested by a treatise on the science of dosage
form design, which would have then showed that no enteric coating was
necessary.

   The Federal Circuit held that the patent was invalid because the claimed
formulation was obvious. The Federal Circuit reasoned that the prior art
would have funneled the formulator toward two options. Thus, the formulator
would not have been required to try all possibilities in a field unreduced
by the prior art. The prior art was not vague in pointing toward a general
approach or area of exploration, but rather guided the formulator precisely
to the use of either a normal pill or an enteric-coated pill.

   It is important for Office personnel to recognize that the mere
existence of a large number of options does not in and of itself lead to a
conclusion of nonobviousness. Where the prior art teachings lead one of
ordinary skill in the art to a narrower set of options, then that reduced
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set is the appropriate one to consider when determining obviousness using
an obvious to try rationale.

   Example 4.18. Sanofi-Synthelabo v. Apotex, Inc., 550 F.3d 1075 (Fed.
Cir. 2008). Teaching point: A claimed isolated stereoisomer would not have
been obvious where the claimed stereoisomer exhibits unexpectedly strong
therapeutic advantages over the prior art racemic mixture without the
correspondingly expected toxicity, and the resulting properties of the
enantiomers separated from the racemic mixture were unpredictable.

   The case of Sanofi also sheds light on the obvious to try line of
reasoning. The claimed compound was clopidogrel, which is the
dextrorotatory isomer of methyl alpha-5(4,5,6,7-tetrahydro(3,2-
c)thienopyridyl)(2-chlorophenyl)-acetate. Clopidogrel is an anti-thrombotic
compound used to treat or prevent heart attack or stroke. The racemate, or
mixture of dextrorotatory and levorotatory (D- and L-) isomers of the
compound, was known in the prior art. The two forms had not previously been
separated, and although the mixture was known to have anti-thrombotic
properties, the extent to which each of the individual isomers contributed
to the observed properties of the racemate was not known and was not
predictable.

   The district court assumed that in the absence of any additional
information, the D-isomer would have been prima facie obvious over the
known racemate. However, in view of the evidence of unpredicted therapeutic
advantages of the D-isomer presented in the case, the district court found
that any prima facie case of obviousness had been overcome. At trial, the
experts for both parties testified that persons of ordinary skill in the
art could not have predicted the degree to which the isomers would have
exhibited different levels of therapeutic activity and toxicity. Both
parties' experts also agreed that the isomer with greater therapeutic
activity would most likely have had greater toxicity. Sanofi witnesses
testified that Sanofi's own researchers had believed that the separation of
the isomers was unlikely to have been productive, and experts for both
parties agreed that it was difficult to separate isomers at the time of the
invention. Nevertheless, when Sanofi ultimately undertook the task of
separating the isomers, it found that they had the "rare characteristic of
`absolute stereoselectivity,'" whereby the D-isomer provided all of the
favorable therapeutic activity but no significant toxicity, while the
L-isomer produced no therapeutic activity but virtually all of the
toxicity. Based on this record, the district court concluded that Apotex
had not met its burden of proving by clear and convincing evidence that
Sanofi's patent was invalid for obviousness. The Federal Circuit affirmed
the district court's conclusion.

   Office personnel should recognize that even when only a small number of
possible choices exist, the obvious to try line of reasoning is not
appropriate when, upon consideration of all of the evidence, the outcome
would not have been reasonably predictable and the inventor would not have
had a reasonable expectation of success. In Bayer, there were art-based
reasons to expect that both the normal pill and the enteric-coated pill
would be therapeutically suitable, even though not all prior art studies
were in complete agreement. Thus, the result obtained was not unexpected.
In Sanofi, on the other hand, there was strong evidence that persons of
ordinary skill in the art, prior to the separation of the isomers, would
have had no reason to expect that the D-isomer would have such strong
therapeutic advantages as compared with the L-isomer. In other words, the
result in Sanofi was unexpected.

   Example 4.19. Rolls-Royce, PLC v. United Technologies Corp., 603 F.3d
1325 (Fed. Cir. 2010). Teaching point: An obvious to try rationale may be
proper when the possible options for solving a problem were known and
finite. However, if the possible options were not either known or finite,
then an obvious to try rationale cannot be used to support a conclusion of
obviousness.

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   In Rolls-Royce the Federal Circuit addressed the obvious to try
rationale in the context of a fan blade for jet engines. The case had
arisen out of an interference proceeding. Finding that the district court
had correctly determined that there was no interference-in-fact because
Rolls-Royce's claims would not have been obvious in light of United's
application, the Federal Circuit affirmed.

   The Federal Circuit described the fan blade of the count as follows:

   Each fan blade has three regions - an inner, an intermediate, and an
outer region. The area closest to the axis of rotation at the hub is the
inner region. The area farthest from the center of the engine and closest
to the casing surrounding the engine is the outer region. The intermediate
region falls in between. The count defines a fan blade with a swept-
forward inner region, a swept-rearward intermediate region, and forward-
leaning outer region.

   Id. at 1328.

   United had argued that it would have been obvious for a person of
ordinary skill in the art to try a fan blade design in which the sweep
angle in the outer region was reversed as compared with prior art fan
blades from rearward to forward sweep, in order to reduce endwall shock.
The Federal Circuit disagreed with United's assessment that the claimed fan
blade would have been obvious based on an obvious to try rationale. The
Federal Circuit pointed out that in a proper obvious to try approach to
obviousness, the possible options for solving a problem must have been
"known and finite." Id. at 1339, citing Abbott, 544 F.3d at 1351. In this
case, there had been no suggestion in the prior art that would have
suggested that changing the sweep angle as Rolls-Royce had done would have
addressed the issue of endwall shock. Thus, the Federal Circuit concluded
that changing the sweep angle "would not have presented itself as an option
at all, let alone an option that would have been obvious to try." Rolls-
Royce, 603 F.3d at 1339. The decision in Rolls-Royce is a reminder to
Office personnel that the obvious to try rationale can properly be used to
support a conclusion of obviousness only when the claimed solution would
have been selected from a finite number of potential solutions known to
persons of ordinary skill in the art.

   Example 4.20. Perfect Web Technologies, Inc. v. InfoUSA, Inc., 587 F.3d
1324, 1328-29 (Fed. Cir. 2009). Teaching point: Where there were a finite
number of identified, predictable solutions and there is no evidence of
unexpected results, an obvious to try inquiry may properly lead to a legal
conclusion of obviousness. Common sense may be used to support a legal
conclusion of obviousness so long as it is explained with sufficient
reasoning.

   The Perfect Web case provides an example in which the Federal Circuit
held that a claimed method for managing bulk e-mail distribution was
obvious on the basis of an obvious to try argument. In Perfect Web, the
method required selecting the intended recipients, transmitting the
e-mails, determining how many of the e-mails had been successfully
received, and repeating the first three steps if a pre-determined minimum
number of intended recipients had not received the e-mail.

   The Federal Circuit affirmed the district court's determination on
summary judgment that the claimed invention would have been obvious.
Failure to meet a desired quota of e-mail recipients was a recognized
problem in the field of e-mail marketing. The prior art had also
recognized three potential solutions: Increasing the size of the initial
recipient list; resending e-mails to recipients who did not receive them on
the first attempt; and selecting a new recipient list and sending e-mails
to them. The last option corresponded to the fourth step of the invention
as claimed.

   The Federal Circuit noted that based on "simple logic," selecting a new
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list of recipients was more likely to result in the desired outcome than
resending to those who had not received the e-mail on the first attempt.
There had been no evidence of any unexpected result associated with
selecting a new recipient list, and no evidence that the method would not
have had a reasonable likelihood of success. Thus, the Federal Circuit
concluded that, as required by KSR, there were a "finite number of
identified, predictable solutions," and that the obvious to try inquiry
properly led to the legal conclusion of obviousness.

   The Federal Circuit in Perfect Web also discussed the role of common
sense in the determination of obviousness. The district court had cited KSR
for the proposition that "[a] person of ordinary skill is also a person of
ordinary creativity, not an automaton," and found that "the final step [of
the claimed invention] is merely the logical result of common sense
application of the maxim `try, try again.'" In affirming the district
court, the Federal Circuit undertook an extended discussion of common sense
as it has been applied to the obviousness inquiry, both before and since
the KSR decision.

   The Federal Circuit pointed out that application of common sense is not
really an innovation in the law of obviousness when it stated, "Common
sense has long been recognized to inform the analysis of obviousness if
explained with sufficient reasoning." Perfect Web, 587 F.3d at 1328
(emphasis added). The Federal Circuit then provided a review of a number of
precedential cases that inform the understanding of common sense, including
In re Bozek, 416 F.2d 1385, 1390 (CCPA 1969) (explaining that a patent
examiner may rely on "common knowledge and common sense of the person of
ordinary skill in the art without any specific hint or suggestion in a
particular reference") and In re Zurko, 258 F.3d 1379, 1383, 1385 (Fed.
Cir. 2001) (clarifying that a factual foundation is needed in order for an
examiner to invoke "good common sense" in a case in which "basic knowledge
and common sense was not based on any evidence in the record").

   The Federal Circuit implicitly acknowledged in Perfect Web that the
kind of strict evidence-based teaching, suggestion, or motivation
required in In re Lee, 277 F.3d 1338, 1344 (Fed. Cir. 2002), is not an
absolute requirement for an obviousness rejection in light of the
teachings of KSR. The Federal Circuit explained that "[a]t the time
[of the Lee decision], we required the PTO to identify record evidence
of a teaching, suggestion, or motivation to combine references."
However, Perfect Web went on to state that even under Lee, common sense
could properly be applied when analyzing evidence relevant to
obviousness. Citing DyStar Textilfarben GmbH v. C.H. Patrick Co., 464
F.3d 1356 (Fed. Cir. 2006), and In re Kahn, 441 F.3d 977 (Fed. Cir.
2006), two cases decided shortly before the Supreme Court's decision in
KSR, the Federal Circuit noted that although "a reasoned explanation
that avoids conclusory generalizations" is required to use common
sense, identification of a "specific hint or suggestion in a
particular reference" is not.

   5. Federal Circuit Cases Discussing Consideration of Evidence.
Office personnel should consider all rebuttal evidence that is timely
presented by the applicants when reevaluating any obviousness
determination. In the case of a claim rendered obvious by a combination
of prior art references, applicants may submit evidence or argument to
demonstrate that the results of the claimed combination were
unexpected.

   Another area that has thus far remained consistent with pre-KSR
precedent is the consideration of rebuttal evidence and secondary
considerations in the determination of obviousness. As reflected in the
MPEP, such evidence should not be considered simply for its
"knockdown" value; rather, all evidence must be reweighed to
determine whether the claims are nonobvious.

   Once the applicant has presented rebuttal evidence, Office
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personnel should reconsider any initial obviousness determination in
view of the entire record. See, e.g., In re Piasecki, 745 F.2d 1468,
1472, 223 USPQ 785, 788 (Fed. Cir. 1984); In re Eli Lilly & Co., 90
F.2d 943, 945, 14 USPQ2d 1741, 1743 (Fed. Cir. 1990). All the
rejections of record and proposed rejections and their bases should
be reviewed to confirm their continued viability.

   MPEP § 2141.

   Office personnel should not evaluate rebuttal evidence for its
"knockdown" value against the prima facie case, Piasecki, 745 F.2d
at 1473, 223 USPQ at 788, or summarily dismiss it as not compelling
or insufficient. If the evidence is deemed insufficient to rebut the
prima facie case of obviousness, Office personnel should
specifically set forth the facts and reasoning that justify this
conclusion.

   MPEP § 2145. The following cases exemplify the continued
application of these principles both at the Federal Circuit and within
the Office. Note that these principles were at issue in some of the
cases previously discussed, and have been addressed there in a more
cursory fashion.
   Example 5.1. PharmaStem Therapeutics, Inc. v. Viacell, Inc., 491
F.3d 1342 (Fed. Cir. 2007). Teaching point: Even though all evidence
must be considered in an obviousness analysis, evidence of
nonobviousness may be outweighed by contradictory evidence in the
record or by what is in the specification. Although a reasonable
expectation of success is needed to support a case of obviousness,
absolute predictability is not required.

   The claims at issue in PharmaStem were directed to compositions
comprising hematopoietic stem cells from umbilical cord or placental
blood, and to methods of using such compositions for treatment of blood
and immune system disorders. The composition claims required that the
stem cells be present in an amount sufficient to effect hematopoietic
reconstitution when administered to a human adult. The trial court had
found that PharmaStem's patents were infringed and not invalid on
obviousness or other grounds. On appeal, the Federal Circuit reversed
the district court, determining that the claims were invalid for
obviousness.

   The Federal Circuit discussed the evidence presented at trial. It
pointed out that the patentee, PharmaStem, had not invented an entirely
new procedure or new composition. Rather, PharmaStem's own
specification acknowledged that it was already known in the prior art
that umbilical cord and placental blood-based compositions contained
hematopoietic stem cells, and that hematopoietic stem cells were useful
for the purpose of hematopoietic reconstitution. PharmaStem's
contribution was to provide experimental proof that umbilical cord and
placental blood could be used to effect hematopoietic reconstitution in
mice. By extrapolation, one of ordinary skill in the art would have
expected this reconstitution method to work in humans as well.

   The court rejected PharmaStem's expert testimony that hematopoietic
stem cells had not been proved to exist in cord blood prior to the
experiments described in PharmaStem's patents. The court explained that
the expert testimony was contrary to the inventors' admissions in the
specification, as well as prior art teachings that disclosed stem cells
in cord blood. In this case, PharmaStem's evidence of nonobviousness
was outweighed by contradictory evidence.

   Despite PharmaStem's useful experimental validation of
hematopoietic reconstitution using hematopoietic stem cells from
umbilical cord and placental blood, the Federal Circuit found that the
claims at issue would have been obvious. There had been ample
suggestion in the prior art that the claimed method would have worked.
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Absolute predictability is not a necessary prerequisite to a case of
obviousness. Rather, a degree of predictability that one of ordinary
skill would have found to be reasonable is sufficient. The Federal
Circuit concluded that "[g]ood science and useful contributions do not
necessarily result in patentability." Id. at 1364.

   Example 5.2. In re Sullivan, 498 F.3d 1345 (Fed. Cir. 2007).
Teaching point: All evidence, including evidence rebutting a prima
facie case of obviousness, must be considered when properly presented.

   It was found to be an error in Sullivan for the Board to fail to
consider evidence submitted to rebut a prima facie case of obviousness.

   The claimed invention was directed to an antivenom composition
comprising F(ab) fragments used to treat venomous rattlesnake bites.
The composition was created from antibody molecules that include three
fragments, F(ab)2, F(ab) and F(c), which have separate
properties and utilities. There have been commercially available
antivenom products that consisted of whole antibodies and
F(ab)2 fragments, but researchers had not experimented with
antivenoms containing only F(ab) fragments because it was believed that
their unique properties would prevent them from decreasing the toxicity
of snake venom. The inventor, Sullivan, discovered that F(ab) fragments
are effective at neutralizing the lethality of rattlesnake venom, while
reducing the occurrence of adverse immune reactions in humans. On
appeal of the examiner's rejection, the Board held that the claim was
obvious because all the elements of the claimed composition were
accounted for in the prior art, and that the composition taught by that
prior art would have been expected by a person of ordinary skill in the
art at the time the invention was made to neutralize the lethality of
the venom of a rattlesnake.

   Rebuttal evidence had not been considered by the Board because it
considered the evidence to relate to the intended use of the claimed
composition as an antivenom, rather than the composition itself.
Appellant successfully argued that even if the Board had shown a prima
facie case of obviousness, the extensive rebuttal evidence must be
considered. The evidence included three expert declarations submitted
to show that the prior art taught away from the claimed invention, an
unexpected property or result from the use of F(ab) fragment antivenom,
and why those having ordinary skill in the art expected antivenoms
comprising F(ab) fragments to fail. The declarations related to more
than the use of the claimed composition. While a statement of intended
use may not render a known composition patentable, the claimed
composition was not known, and whether it would have been obvious
depends upon consideration of the rebuttal evidence. Appellant did not
concede that the only distinguishing factor of its composition is the
statement of intended use and extensively argued that its claimed
composition exhibits the unexpected property of neutralizing the
lethality of rattlesnake venom while reducing the occurrence of adverse
immune reactions in humans. The Federal Circuit found that such a use
and unexpected property cannot be ignored - the unexpected property is
relevant and thus the declarations describing it should have been
considered.

   Nonobviousness can be shown when a person of ordinary skill in the
art would not have reasonably predicted the claimed invention based on
the prior art, and the resulting invention would not have been
expected. All evidence must be considered when properly presented.

   Example 5.3. Hearing Components, Inc. v. Shure Inc., 600 F.3d 1357
(Fed. Cir. 2010). Teaching point: Evidence that has been properly
presented in a timely manner must be considered on the record. Evidence
of commercial success is pertinent where a nexus between the success of
the product and the claimed invention has been demonstrated.

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   The case of Hearing Components involved a disposable protective
covering for the portion of a hearing aid that is inserted into the ear
canal. The covering was such that it could be readily replaced by a
user as needed.

   At the district court, Shure had argued that Hearing Components'
patents were obvious over one or more of three different combinations
of prior art references. The jury disagreed, and determined that the
claims were nonobvious. The district court upheld the jury verdict,
stating that in view of the conflicting evidence presented by the
parties as to the teachings of the references, motivation to combine,
and secondary considerations, the nonobviousness verdict was
sufficiently grounded in the evidence.

   Shure appealed to the Federal Circuit, but the Federal Circuit
agreed with the district court that the jury's nonobviousness verdict
had been supported by substantial evidence. Although Shure had argued
before the jury that the Carlisle reference taught an ear piece
positioned inside the ear canal, Hearing Components' credible witness
countered that only the molded duct and not the ear piece itself was
taught by Carlisle as being inside the ear canal. On the issue of
combining references, Shure's witness had given testimony described as
"rather sparse, and lacking in specific details." Id. at 1364. In
contradistinction, Hearing Components' witness "described particular
reasons why one skilled in the art would not have been motivated to
combine the references." Id. Finally, as to secondary considerations,
the Federal Circuit determined that Hearing Components had shown a
nexus between the commercial success of its product and the patent by
providing evidence that "the licensing fee for a covered product was
more than cut in half immediately upon expiration" of the patent.

   Although the Hearing Components case involves substantial evidence
of nonobviousness in a jury verdict, it is nevertheless instructive for
Office personnel on the matter of weighing evidence. Office personnel
routinely must consider evidence in the form of prior art references,
statements in the specification, or declarations under 37 CFR 1.131 or
1.132. Other forms of evidence may also be presented during
prosecution. Office personnel are reminded that evidence that has been
presented in a timely manner should not be ignored, but rather should
be considered on the record. However, not all evidence need be accorded
the same weight. In determining the relative weight to accord to
rebuttal evidence, considerations such as whether a nexus exists
between the claimed invention and the proffered evidence, and whether
the evidence is commensurate in scope with the claimed invention, are
appropriate. The mere presence of some credible rebuttal evidence does
not dictate that an obviousness rejection must always be withdrawn. See
MPEP § 2145. Office personnel must consider the appropriate weight
to be accorded to each piece of evidence. An obviousness rejection
should be made or maintained only if evidence of obviousness outweighs
evidence of nonobviousness. See MPEP § 706(I) ("The standard to be
applied in all cases is the `preponderance of the evidence' test. In
other words, an examiner should reject a claim if, in view of the prior
art and evidence of record, it is more likely than not that the claim
is unpatentable."). MPEP § 716.01(d) provides further guidance on
weighing evidence in making a determination of patentability.

   Example 5.4. Asyst Techs., Inc. v. Emtrak, Inc., 544 F.3d 1310
(Fed. Cir. 2008). Teaching point: Evidence of secondary considerations
of obviousness such as commercial success and long-felt need may be
insufficient to overcome a prima facie case of obviousness if the prima
facie case is strong. An argument for nonobviousness based on
commercial success or long-felt need is undermined when there is a
failure to link the commercial success or long-felt need to a claimed
feature that distinguishes over the prior art.

   The claims at issue in Asyst concerned a processing system for
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tracking articles such as silicon wafers which move from one processing
station to the next in a manufacturing facility. The claims required
that each processing station be in communication with a central control
unit. The Federal Circuit agreed with the district court that the only
difference between the claimed invention and the prior art to Hesser
was that the prior art had taught the use of a bus for this
communication, while the claims required a multiplexer. At trial, the
jury had concluded that Hesser was not relevant prior art, but the
district court overturned that conclusion and issued a judgment as a
matter of law (JMOL) that the claims would have been obvious in view of
Hesser. Because the evidence showed that persons of ordinary skill in
the art would have been familiar with both the bus and the multiplexer,
and that they could have readily selected and employed one or the other
based on known considerations, the Federal Circuit affirmed the
district court's conclusion that the claims were invalid for
obviousness.

   The Federal Circuit also discussed arguments that the district court had
failed to consider the objective evidence of nonobviousness presented by
Asyst. Asyst had offered evidence of commercial success of its invention.
However, the Federal Circuit pointed out that Asyst had not provided the
required nexus between the commercial success and the claimed invention,
emphasizing that "Asyst's failure to link that commercial success to the
features of its invention that were not disclosed in Hesser undermines the
probative force of the evidence * * *." Id. at 1316. Asyst had also
offered evidence from others in the field praising the invention as
addressing a long-felt need. Once again, the Federal Circuit found the
argument to be unavailing in view of the prior art, stating that
"[w]hile the evidence shows that the overall system drew praise as a
solution to a felt need, there was no evidence that the success * * *
was attributable to the substitution of a multiplexer for a bus, which
was the only material difference between Hesser and the patented
invention." Id. The Federal Circuit also reiterated, citing pre-KSR
decisions, that "as we have often held, evidence of secondary
considerations does not always overcome a strong prima facie showing of
obviousness." Id. (citing Pfizer, Inc. v. Apotex, Inc., 480 F.3d 1348,
1372 (Fed. Cir. 2007); Ryko Mfg. Co. v. Nu-Star, Inc., 950 F.2d 714,
719-20 (Fed. Cir. 1991); Newell Cos. v. Kenney Mfg. Co., 864 F.2d 757,
768 (Fed. Cir. 1988)).

   When considering obviousness, Office personnel should carefully
weigh any properly presented objective evidence of nonobviousness
against the strength of the prima facie case. If the asserted evidence,
such as commercial success or satisfaction of a long-felt need, is
attributable to features already in the prior art, the probative value
of the evidence is reduced.

   6. Conclusion. This 2010 KSR Guidelines Update is intended to be
used by Office personnel in conjunction with the guidance provided in
MPEP Sec. § 2141 and 2143 (which incorporates the 2007 KSR
Guidelines) to clarify the contours of obviousness after KSR. It
addresses a number of issues that arise when Office personnel consider
whether or not a claimed invention is obvious. While Office personnel
are encouraged to make use of these tools, they are reminded that every
question of obviousness must be decided on its own facts. The Office
will continue to monitor the developing law of obviousness, and will
provide additional guidance and updates as necessary.

August 20, 2010                                             DAVID J. KAPPOS
                                            Under Secretary of Commerce for
                                  Intellectual Property and Director of the
                                  United States Patent and Trademark Office

Appendix

   The following table contains the cases set out as examples in
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this 2010 KSR Guidelines Update and the teaching points of the case.

          Case                          Teaching point

                         Combining Prior Art Elements

In re Omeprazole Patent         Even where a general method that
Litigation, 536 F.3d 1361       could have been applied to make the
(Fed. Cir. 2008).               claimed product was known and
                                within the level of skill of the
                                ordinary artisan, the claim may
                                nevertheless be nonobvious if the
                                problem which had suggested use of
                                the method had been previously
                                unknown.
Crocs, Inc. v. U.S. Int'l       A claimed combination of prior art
Trade Comm'n., 598 F.3d         elements may be nonobvious where
1294 (Fed. Cir. 2010).          the prior art teaches away from the
                                claimed combination and the
                                combination yields more than
                                predictable results.
Sundance, Inc. v. DeMonte       A claimed invention is likely to be
Fabricating Ltd., 550 F.3d      obvious if it is a combination of
1356 (Fed. Cir. 2008).          known prior art elements that would
                                reasonably have been expected to
                                maintain their respective
                                properties or functions after they
                                have been combined.
Ecolab, Inc. v. FMC Corp.,      A combination of known elements
569 F.3d 1335 (Fed. Cir.        would have been prima facie obvious
2009).                          if an ordinarily skilled artisan
                                would have recognized an apparent
                                reason to combine those elements
                                and would have known how to do so.
Wyers v. Master Lock Co.,       The scope of analogous art is to be
No. 2009-1412, -F.3d-,          construed broadly and includes
2010 WL 2901839 (Fed.           references that are reasonably
Cir. July 22, 2010).            pertinent to the problem that the
                                inventor was trying to solve.
                                Common sense may be used to support
                                a legal conclusion of obviousness
                                so long as it is explained with
                                sufficient reasoning.
DePuy Spine, Inc. v.            Predictability as discussed in KSR
Medtronic Sofamor Danek,        encompasses the expectation that
Inc., 567 F.3d 1314             prior art elements are capable of
(Fed. Cir. 2009).               being combined, as well as the
                                expectation that the combination
                                would have worked for its intended
                                purpose. An inference that a
                                claimed combination would not have
                                been obvious is especially strong
                                where the prior art's teachings
                                undermine the very reason being
                                proffered as to why a person of
                                ordinary skill would have combined
                                the known elements.

                  Substituting One Known Element for Another

In re ICON Health & Fitness,    When determining whether a reference
Inc., 496 F.3d 1374 (Fed.       in a different field of endeavor
Cir. 2007).                     may be used to support a case of
                                obviousness (i.e., is analogous),
                                it is necessary to consider the
                                problem to be solved.
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                                Agrizap, Inc. v. Woodstream
                                Analogous art is not limited to
Corp., 520 F.3d 1337 (Fed.      references in the field of endeavor
Cir. 2008).                     of the invention, but also includes
                                references that would have been
                                recognized by those of ordinary
                                skill in the art as useful for
                                applicant's purpose.
Muniauction, Inc. v.            Because Internet and Web browser
Thomson Corp., 532 F.3d         technologies had become commonplace
1318 (Fed. Cir. 2008).          for communicating and displaying
                                information, it would have been
                                obvious to adapt existing processes
                                to incorporate them for those
                                functions.
Aventis Pharma Deutschland      A chemical compound would have been
v. Lupin, Ltd., 499 F.3d        obvious over a mixture containing
1293 (Fed. Cir. 2007).          that compound as well as other
                                compounds where it was known or the
                                skilled artisan had reason to
                                believe that some desirable
                                property of the mixture was derived
                                in whole or in part from the
                                claimed compound, and separating
                                the claimed compound from the
                                mixture was routine in the art.
Eisai Co. Ltd. v.               A claimed compound would not have
Dr. Reddy's Labs., Ltd.,        been obvious where there was no
533 F.3d 1353 (Fed. Cir.        reason to modify the closest prior
2008).                          art lead compound to obtain the
                                claimed compound and the prior art
                                taught that modifying the lead
                                compound would destroy its
                                advantageous property. Any known
                                compound may serve as a lead
                                compound when there is some reason
                                for starting with that lead
                                compound and modifying it to obtain
                                the claimed compound.
Procter & Gamble Co. v.         It is not necessary to select a
Teva Pharmaceuticals USA,       single compound as a "lead
Inc., 566 F.3d 989              compound" in order to support an
(Fed. Cir. 2009).               obviousness rejection. However,
                                where there was reason to select
                                and modify the lead compound to
                                obtain the claimed compound, but no
                                reasonable expectation of success,
                                the claimed compound would not have
                                been obvious.
Altana Pharma AG v.             Obviousness of a chemical compound
Teva Pharms. USA, Inc.,         in view of its structural
566 F.3d 999                    similarity to a prior art compound
(Fed. Cir. 2009).               may be shown by identifying some
                                line of reasoning that would have
                                led one of ordinary skill in the
                                art to select and modify a prior
                                art lead compound in a particular
                                way to produce the claimed
                                compound. It is not necessary for
                                the reasoning to be explicitly
                                found in the prior art of record,
                                nor is it necessary for the prior
                                art to point to only a single lead
                                compound.

                         The Obvious To Try Rationale
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In re Kubin, 561 F.3d           A claimed polynucleotide would have
1351 (Fed. Cir. 2009).          been obvious over the known protein
                                that it encodes where the skilled
                                artisan would have had a reasonable
                                expectation of success in deriving
                                the claimed polynucleotide using
                                standard biochemical techniques,
                                and the skilled artisan would have
                                had a reason to try to isolate the
                                claimed polynucleotide. KSR applies
                                to all technologies, rather than
                                just the "predictable" arts.
Takeda Chem. Indus. v.          A claimed compound would not have
Alphapharm Pty., Ltd.,          been obvious where it was not
492 F.3d 1350                   obvious to try to obtain it from a
(Fed. Cir. 2007).               broad range of compounds, any one
                                of which could have been selected
                                as the lead compound for further
                                investigation, and the prior art
                                taught away from using a particular
                                lead compound, and there was no
                                predictability or reasonable
                                expectation of success in making
                                the particular modifications
                                necessary to transform the lead
                                compound into the claimed compound.
Ortho-McNeil Pharmaceutical,    Where the claimed anti-convulsant
Inc. v. Mylan Labs, Inc.,       drug had been discovered somewhat
520 F.3d 1358                   serendipitously in the course of
(Fed. Cir. 2008).               research aimed at finding a new
                                anti-diabetic drug, it would not
                                have been obvious to try to obtain
                                a claimed compound where the prior
                                art did not present a finite and
                                easily traversed number of
                                potential starting compounds, and
                                there was no apparent reason for
                                selecting a particular starting
                                compound from among a number of
                                unpredictable alternatives.
Bayer Schering Pharma A.G.      A claimed compound would have been
v. Barr Labs., Inc.,            obvious where it was obvious to try
575 F.3d 1341                   to obtain it from a finite and
(Fed. Cir. 2009).               easily traversed number of options
                                that was narrowed down from a
                                larger set of possibilities by the
                                prior art, and the outcome of
                                obtaining the claimed compound was
                                reasonably predictable.Sanofi-Synthelabo v.
                                A claimed isolated stereoisomer
Apotex, Inc., 550               would not have been obvious where
F.3d 1075                       the claimed stereoisomer exhibits
(Fed. Cir. 2008).               unexpectedly strong therapeutic
                                advantages over the prior art
                                racemic mixture without the
                                correspondingly expected toxicity,
                                and the resulting properties of the
                                enantiomers separated from the
                                racemic mixture were unpredictable.
Rolls-Royce, PLC v.             An obvious to try rationale may be
United Technologies Corp.,      proper when the possible options
603 F.3d 1325                   for solving a problem were known
(Fed. Cir. 2010).               and finite. However, if the
                                possible options were not either
                                known or finite, then an obvious to
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                                try rationale cannot be used to
                                support a conclusion of obviousness.
Perfect Web Techs., Inc. v.     Where there were a finite number of
InfoUSA, Inc., 587 F.3d 1324    identified, predictable solutions
(Fed. Cir. 2009).               and there is no evidence of
                                unexpected results, an obvious to
                                try inquiry may properly lead to a
                                legal conclusion of obviousness.
                                Common sense may be used to support
                                a legal conclusion of obviousness
                                so long as it is explained with
                                sufficient reasoning.

                           Consideration of Evidence

PharmaStem Therapeutics,        Even though all evidence must be
Inc. v. ViaCell, Inc.,          considered in an obviousness
491 F.3d 1342                   analysis, evidence of
(Fed. Cir. 2007).               nonobviousness may be outweighed by
                                contradictory evidence in the
                                record or by what is in the
                                specification. Although a
                                reasonable expectation of success
                                is needed to support a case of
                                obviousness, absolute
                                predictability is not required.
In re Sullivan, 498 F.3d        All evidence, including evidence
1345 (Fed. Cir. 2007).          rebutting a prima facie case of
                                obviousness, must be considered
                                when properly presented.
Hearing Components, Inc.        Evidence that has been properly
v. Shure Inc., 600 F.3d         presented in a timely manner must
1357 (Fed. Cir. 2010).          be considered on the record.
                                Evidence of commercial success is
                                pertinent where a nexus between the
                                success of the product and the
                                claimed invention has been demonstrated.
Asyst Techs., Inc. v.           Evidence of secondary considerations
Emtrak, Inc., 544 F.3d          of obviousness such as commercial
1310 (Fed. Cir. 2008).          success and long-felt need may be
                                insufficient to overcome a prima
                                facie case of obviousness if the
                                prima facie case is strong. An
                                argument for nonobviousness based
                                on commercial success or long-felt
                                need is undermined when there is a
                                failure to link the commercial
                                success or long-felt need to a
                                claimed feature that distinguishes
                                over the prior art.

                                 [1358 OG 372]