Responding to Office Actions

A USPTO patent examiner may issue several different types of official letters about your application. Below is a description of each type and information on how to respond. It is very important to carefully read the USPTO correspondence to understand what type of response is needed and the time period for filing one.

Types of Official Letters:

  • Office Action
    An Office action is written correspondence from the patent examiner that requires a properly signed written response from the applicant in order for prosecution of the application to continue. Moreover, the reply must be responsive to each ground of rejection and objection made by the examiner. Examples of Office actions include a restriction requirement, a non-final Office action, and a final Office action.
  • Notice of Allowability
    If the patent examiner determines that all of the pending claims in the patent application are allowable (e.g., eligible to receive a patent), then a Notice of Allowability (USPTO Form PTOL-37) will be mailed. The Notice of Allowability will identify the allowable claims and will be accompanied by a Notice of Allowance and Fee(s) Due (USPTO Form PTOL-85) identifying what fee(s) must be timely paid before issuance of the patent application as a U.S. Patent.
  • Notice
    Another type of notice may be mailed by the examiner to identify one or more deficiencies in the patent application or in applicant's correspondence. A notice usually sets a two-month time period to correct the deficiency unless it accompanies an Office action. An example of a notice is a Notice of Non-Compliant Amendment(37 CFR 1.121).

Response Deadlines

Most replies to Office actions (official letters) must be received within 6 months from the mailing date on the Office action. Office actions in almost all instances set a shortened period within which a response can be filed without having to pay extension of time fees. The shortened period is typically either two or three months, depending on the type of Office action. In certain circumstances, the Office action will specify a different response period. There are no extensions beyond the 6-month statutory time period for reply other than notices that do not have a statutory time period for reply. If an applicant does not submit an acceptable timely response to an Office action, the application will be held abandoned.

How to Respond to Official Letters

The USPTO transacts business in writing. Applicants may submit replies to Office actions:

  • online via the USPTO's Patent Center (Registered eFilers only);
  • by mail;
  • by facsimile to the USPTO's Official Fax Number (571-273-8300); or
  • by hand-carry to USPTO's Alexandria, Virginia Customer Service Window.

Registered users of the USPTO's Patent Center may submit a response electronically through Patent Center All correspondence filed via Patent Center is time/date stamped when received on the USPTO server, according to Eastern Time and such receipt time controls for purposes of determining the timeliness of a document. Any submission that arrives as of 11:59 p.m. Eastern Time will be given that day's filing date (i.e., regardless of the USPTO's "normal" business hours).

Responses may also be submitted by mail, facsimile, or hand carried to USPTO's Customer Service Window in Alexandria, Virginia. If the response is deposited with the United States Postal Service with sufficient postage as first class mail, the response will receive the benefit of the date of deposit for timeliness purposes if accompanied by a signed, completed certificate of mailing. If the response is facsimile transmitted to the USPTO's Official Fax Number (571-273-8300), the response will receive the benefit of the date of transmission if accompanied by a signed, completed certificate of transmission. Information about certificate of mailing and certificate of transmission can be found at: Applicants should retain a photocopy of the response with the signed certificate in the event that the response is lost or misplaced by the Office.

Responses that are mailed to the USPTO from outside of the United States or hand carried to the Customer Service Window will receive the actual date of receipt for timeliness purposes.