Patent Enforcement

A patent grants the right to exclude others from making, selling and using an invention.  This right is enforceable in a design patent for a term of 14 years, which is measured from its issue dateUtility patents are enforceable for a term of 20 years, which is measured from its filing date or priority date, barring any patent term adjustment.  See 35 USC 154.

Whoever makes, uses, sells, offers to sell or imports a patented invention, without authorization from the patent owner, infringes the patent.  Whoever induces someone to infringe is also liable for infringement.   See 35 USC 271

Patent owners have to provide notice of infringement.  This should be done by marking patented products or its packaging as patented (i.e., "Patent US” followed by the patent number).  If the product is not marked, the patent owner may not recover damages for infringement unless the owner gives actual notice and the infringement continues.  In this case, damages may be recovered only for the infringement occurring after the notice is given.  See 35 USC 287.

The actual notice is usually in the form of a letter referred to as a cease and desist letter.  The letter must identify the infringed patent (i.e., by patent number), refer to a specific infringing product (i.e., the “accused product”), and communicate an unequivocal accusation of infringement

There is a risk that sending a cease and desist letter may solicit from the infringer a response in the form of a declaratory judgment suit (i.e., a suit asking for a court to find that the patent is invalid, unenforceable, or not infringed).  This may present certain disadvantages to the patent owner, such as unfavorable timing or venue (i.e., the place of suit). 

Once notice is provided, the patent owner should be prepared to bring suit against the infringer if the infringer does not respond accordingly.  Failure to bring suit may give rise to an estoppel defense by the infringer.  Estoppel is a legal doctrine that permits the infringer to rely on the patent owner’s inaction as acquiescence to the infringer’s conduct, which may prevent the patent owner from enforcing its rights in the patent. 

There is another risk to a patent owner if the patent owner fails to bring suit.  If the patent owner knows or should have known of some infringement and does nothing, the patent owner may forfeit its rights under another legal doctrine referred to as laches

Whether plaintiff or defendant, another factor to consider is the cost of patent litigation.  Depending on the amount in controversy, the cost (i.e., attorney's fees and expenses) of patent litigation could easily exceed $1 million USD, which does not include damages that the defendant has to pay if the defendant loses.  It may be more cost effective (i.e., a better business decision) to settle the suit, especially for small business defendants, even if the defendant does not infringe the patent. 

For patent owners that may not be able to afford patent litigation, a solid case of infringement may attract the attention of an attorney who will take the case for a contingent fee and may find an investor to cover the expenses.  However, before committing to do so, the attorney will have to carefully evaluate the case because if an unfavorable verdict is reached, the attorney receives no compensation and any investment in the litigation is lost. 

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