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How does a patent infringement lawsuit begin?

A patent lawsuit begins with the filing of a complaint alleging patent infringement by the patent holder. If a lawsuit is filed against you, the patent owner must serve two documents on you: (1) a document called a “complaint,” which explains the accusations made against you; and (2) a document called a “summons.” The patent owner may first send a “demand” letter that states that you are potentially infringing the claims of a patent and request that you pay for a license to use the patented invention, or it may go straight to court.

 

What are my options for responding to the suit?

If you are sued, you must formally respond. The response must be filed with the court within the time period set and a copy must be served on the patent owner. Otherwise, the court may enter a default judgment against you, which may order you to pay damages and/or stop infringing on one or more patent claims. While you should contact an attorney familiar with patents to assist and help you decide on the best course of action, if you are sued, your options include:

  • Denying that the patent owner has proved that you infringe any claim of the patent or patents.
  • Negotiating with the patent owner for settlement of the lawsuit, for example, by agreeing to a license or a statement that you do not infringe the patent. A mediator may help you reach an agreeable settlement.
  • Trying to invalidate the patent based on references that show that the patent or patents are invalid.

These options may be pursued in or outside of court, but court-based litigation is often very expensive (costing hundreds of thousands to millions of dollars) and slow, regularly taking several years before the court will reach a verdict. Even if the case results in a court decision, it may then be appealed to the Federal Circuit, and potentially the Supreme Court, requiring additional time and money.

 

How can I tell whether or not I’m infringing?

To determine whether or not you are infringing a patent, you or your attorney would need to compare a patent’s claims and the accused product, system, or process. To infringe a patent, the accused must perform each and every element of one or more of its claims, or actively encourage, sell or offer to sell a component that leads to another’s infringement. The best way to understand each claim is in light of the description provided through the patent (called the “specification”). A person knowledgeable in the technology should be able to read the specification and be able to tell how to make and use the invention.

The written record created when the USPTO examined the patent application, called the "prosecution history" or “file wrapper”, provides further context for understanding the boundaries of the claims,  especially with respect to the closest “prior art.” Prior art consists of the references (books, articles, web pages and other information) that were publicly available before the date that the application was filed. For many patents, the prosecution history is available for free via the USPTO Public PAIR (Patent Application Information Retrieval) website. If the prosecution history is not available on Public PAIR, you may order it online on the USPTO website. A registered patent attorney or patent agent can advise you regarding all of the above.

 

How do I find a lawyer?

Only an attorney can represent you in court. A list of registered patent agents and patent attorneys can be found at the embedded link. However, please note that not all of the attorneys listed provide representation in patent litigation matters. The state bar association where you or your business is located and any one of the national bar associations have additional directories of attorneys that may be able to assist you. For more information on local assistance, please visit the Resources webpage. Legal aid organizations and law school clinics may also be of assistance; check the organizations listed in the Resources section of this website. Most limit their services based upon income, the subject matter of the case, and the number of attorneys available.  

Legal aid organizations and law school clinics may also be of assistance; check the organizations listed in the Resources section of this website.

 

Has anyone been sued over the patent?

Understanding whether this particular patent or patents have been litigated before can help you determine your next steps.  See the Resources section of this website for websites that offer to tell you, for free, if the patent has been the subject of a lawsuit. If you find another person with a similar problem, you may consider reaching out to explore ways that you can work together.

 

How can I find out more information about the patent and who is behind the demand?

You can search on the USPTO website or a commercial website for a specific patent number and then download a PDF copy of the patent. The Resources section of this website also lists PTO and other sites that can tell you who is listed as the registered owner of the owner and patent portfolio of the patent holder. You can also check Secretary of State records, your State Bar, the internet, and related sources for information about the entity or attorney sending letters.

 

How can I tell whether the patent is valid?

An invention must meet certain threshold criteria of novelty, usefulness and nonobviousness in order to be patented. See this glossary for an explanation of these concepts.   You may challenge the claims in a patent (or patent application) by showing they should not have been granted, or should not be granted, if these criteria are not met. 
For example, the USPTO or a court may conclude that a claim in a patent or application is invalid if the claimed invention was disclosed, for example, in a prior patent or patents, a book, a magazine, a newspaper, a television show or movie, a webpage or other published work before the date of the claimed invention. Even if there are no such publications, a court may conclude that a patent claim is not valid if it is shown by other evidence that the claimed invention was offered for sale in this country or was disclosed to the public before the application for patent was filed. In addition, a court could find the patent invalid because it does not meet other statutory requirements, such as a sufficient written description of the invention, or because it does not describe subject matter that is patentable.  Finally, a court could find that the patent is unenforceable because of wrongdoing by the applicant, such as by defrauding the USPTO.

 

How can I challenge a patent or patent application?

If you have reason to believe that the patent is not valid or otherwise enforceable, there are several ways to challenge it:

  • You can challenge it at the USPTO by filing a request for reexamination of the patent, or by filing an inter partes dispute such as a request for post grant review, inter partes review, or, for certain kinds of financial services patents, a covered business method patent review.
  • You can challenge a patent in court, either when defending yourself in a lawsuit brought against you for patent infringement, or by filing a declaratory judgment (DJ) action requesting the court to hold the patent invalid.
  • You can challenge a patent application by submitting what is termed “prior art” (e.g., references, publications, or descriptions of the disclosures described above made prior to the filing date of the application) to the USPTO. This must be done before the patent issues. You can search for prior art on your own or by “crowdsourcing," that is using an online community to assist with the searching. You can find a patent search “crowdsourcing” websites by performing an internet search. For more information about submitting prior art relevant to a pending patent application (rather than patent), please see our webpage on pre-issuance submissions.
  • An attorney can help advise you about the various options available to challenge patents and patent applications. Please see the section “Do I need an attorney?” for further information.

Links Referenced on This Page:

Glossary of Patent Terms

Inter partes dispute

Pre-issuance submissions

Public PAIR

Reexamination

Registered patent agents and patent attorneys

Resources

Search Patents

The information presented on this site does not constitute legal advice. It should not be considered to replace advice from an attorney. Reference to any specific organizations, attorneys, law firms, corporations, or websites does not constitute endorsement, recommendation, or favoring by the USPTO.

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Last Modified: 07/25/2014 08:22:00 AM