Patent infringement under United States law

In the United States, a valid patent provides its proprietor with the right to exclude others from practicing the invention claimed in that patent. A person who practices that invention without the permission of the patent holder infringes that patent.

More specifically, an infringement occurs where the defendant has made, used, sold, offered to sell, or imported an infringing invention or its equivalent.^[1]

No infringement action may be started until the patent is issued. However, pre-grant protection is available under 35 U.S.C. § 154(d), which allows a patent owner to obtain reasonable royalty damages for certain infringing activities that occurred before patent's date of issuance. This right to obtain provisional damages requires a patent holder to show that (1) the infringing activities occurred after the publication of the patent application, (2) the patented claims are substantially identical to the claims in the published application, and (3) the infringer had "actual notice" of the published patent application.

In 2015, 45% of all patent cases were filed in the Eastern District of Texas in Marshall, and 28% of all patent cases were filed before James Rodney Gilstrap, as this court was known for favoring plaintiffs and for its expertise in patent suits.^[2]