Public domain

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.

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 pending

A notice that a patent application has been filed with the USPTO but has not yet been examined or granted. "Patent pending" provides no legal protection against copying — it simply puts the public on notice that a patent may issue. If a patent does issue, the patentee may be able to collect reasonable royalties going back to the publication date of the application.

Plant patent

A patent covering a new, distinct variety of plant that has been asexually reproduced (through cuttings, grafting, or budding — not seeds). Plant patents are rare, with fewer than 1,500 issued per year. Most plant protection in agriculture uses a separate system: the Plant Variety Protection Act, administered by the USDA rather than the USPTO.

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.

Priority date

The date that determines whether a piece of prior art counts against a patent application. In the US, the priority date is typically the filing date of the earliest application in a patent family to which the current application claims priority. Under the first-to-file system (post-AIA), the inventor with the earliest priority date wins if two people file on the same invention.