So you've discovered an infringing product on the market. What do you do? First, gather as much information as you can about the infringer and the infringing product. Get names, addresses, correspondence, literature, manuals, advertisements, catalogues and anything else to prove your case. Also, take pictures of where the infringing product was found in the market, and purchase it if possible.
You also need to be on record as responding very promptly to a potential infringement. There are several ways to handle the situation, from fighting it out in court to giving up your patent altogether--for a fee. Write a letter to the infringing company requesting one of the following actions:
Request that the infringer buy your patent--either all or part--for a fee that covers past and future sales.
Ask the company to stop infringing and to pay you compensation for what they have sold.
Request that the infringer compensate you for what he or she has sold and that they offer you a licensing or royalty payment agreement on future sales.
Offer a business deal to the infringer in which he or she can continue to sell the product but in turn gives you rights to his or her patents or other products which may complement yours.
Send your letter by certified mail, return-receipt requested, and include a copy of your patent and, if possible, a sample of your product. The kind of response you get will give you insight into what strategy the infringer may take.
Acting promptly with a letter gives you the ability to recover damages for past infringement (assuming you claimed patent protection for your product) and reduces your chances of falling prey to the legal doctrines known as estoppel and laches. These provisions allow the infringer to argue that he or she should be able to continue to infringe because you did not show enough concern to act promptly. Infringers use this argument to get a reduction in the amount of damages they have to pay to the patent holder and to gain the right to continue to infringe in the future. This is another reason you have to police your market and act quickly when you see possible infringement.