Patent citation

Cross-referenced

Patent

A government-granted right that gives an inventor the exclusive right to prevent others from making, using, selling, or importing a patented invention within the country that granted the patent, for a limited time. A patent does not give the owner the right to practice the invention — only the right to exclude others. The US issues three types: utility, design, and plant patents.

Cross-referenced

Prior art

All publicly available information that existed before a patent's priority date that is relevant to the novelty and non-obviousness of the claimed invention. Prior art includes earlier patents, published patent applications, journal articles, product manuals, conference presentations, and anything that was publicly known or in use. Searching prior art before filing is one of the most valuable steps an inventor can take.

Patent family

The set of related patents and applications that share a common priority claim — an original application plus its continuations, divisionals, and foreign counterparts. Members of a family typically share the same earliest filing (priority) date.

Post-grant review (PGR)

A USPTO proceeding to challenge a recently granted patent, within nine months of grant, on almost any ground of invalidity — including eligibility and written description. It is broader than inter partes review, which is narrower and becomes available later.

Patent Cooperation Treaty (PCT)

An international treaty allowing inventors to file a single "PCT application" that preserves the right to seek patent protection in 150+ member countries. A PCT filing buys time — typically 30 months from the priority date — before the applicant must commit to specific national filings. It is not a "world patent"; each country still examines and grants its own patent under its own laws.

Patent expiry

The point at which a patent's term ends and the invention enters the public domain — either at full term or early, when maintenance fees go unpaid. Once a patent expires, anyone may make, use, or sell what it covered: a drug patent expiring is what lets generic versions enter the market. Expired patents amount to a free, fully documented library of proven technology.