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Updated: Jan 9

After some time in business, you may find your company at the receiving end of a letter notifying you of certain patent(s) and/or accusing you or your company of patent infringement. The letter may be a "notice" letter, identifying certain patent(s) the sender wants you or your company to be aware of. Such a letter may set the stage for willful infringement, even if merely an attempt to initiate a license offer. The letter may be a "cease-and-desist" or "demand" letter, demanding that you stop allegedly infringing activity and typically demanding money for alleged injury by this activity.

A demand letter is typically accompanied by a threat of lawsuit in federal court based on the alleged patent infringement. In some cases, a lawsuit has already been filed and is yet to be served. In other cases, the lawsuit has not been filed. In either circumstance, the letter must be addressed swiftly to avoid loss of rights, mitigate any damages, and position your company for the best defense.

Use the following basic tips to know how to respond to a patent infringement notice letter. Know how to react to minimize financial exposure, minimize interruptions to your business, and avoid loss of rights. Take swift action to plan a response. Use a stepwise approach to prepare an informed plan for response.

  1. Review the letter and understand any specific allegations of patent infringement.

  2. Consult with U.S. legal counsel to determine the best course of action. Your counsel should be experienced in patent law and patent litigation in federal courts and administrative proceedings and trials at the U.S. Patent and Trademark Office and the U.S. International Trade Commission.

  3. Determine whether the asserted patents exist, and are in force, and all maintenance fees are up to date.

  4. Determine whether the sender has already filed a complaint with a federal court.

  5. Determine any patent ownership data on record with the U.S. Patent and Trademark Office.

  6. Consider your exposure. How long has the accused product been offered for sale? Are they still on sale? Have there been any sales?

  7. Conduct a thorough investigation to determine if the allegations have merit.

  8. Determine if there are any available defenses, such as prior art or invalidity of the patent. For example, you may have been selling the accused product before the asserted patents were filed. Or you may have evidence that the sender of the letter offered the invention for sale before the patents were filed.

  9. Develop a plan of action if any action is necessary, including denying infringement and refusing to comply, negotiating a license or settlement, challenging patent validity at the U.S. Patent and Trademark Office, filing a federal legal action seeking a judgment of non-infringement, or ceasing the allegedly infringing activity altogether.

  10. Communicate the plan to the patent owner and work towards resolution.

If you have received a letter accusing your company of patent infringement and have questions or concerns, contact us. Our firm has a track record of success representing clients in litigation and trial and representing patent owners and petitioners in post-grant invalidity proceedings at the U.S. Patent and Trademark Office Patent Trial and Appeal Board.

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