Patent Prosecution

Patent prosecution is the process of applying for and negotiating a patent with a patent office — the United States Patent and Trademark Office (USPTO) or a foreign equivalent such as the European Patent Office (EPO). It covers everything from drafting and filing the application through the examiner’s back-and-forth correspondence to allowance and issuance. Despite the name, prosecution is an administrative, collaborative process, not a courtroom fight — the common confusion with patent litigation (enforcing or challenging a granted patent in court) is addressed directly below.

The prosecution process, stage by stage

1. Drafting and filing. Patent counsel prepares the specification, drawings, and claims and files a provisional or nonprovisional application with the patent office. See CASRAI’s guide on provisional patent applications for the 12-month provisional pathway specifically.
2. Examination. The application is assigned to a patent examiner, who searches prior art and reviews the claims against the statutory requirements (novelty, non-obviousness, utility, enablement).
3. Office actions. If the examiner finds an issue, the USPTO issues a written office action — a non-final or final rejection, or a restriction requirement — citing prior art and explaining the grounds for rejecting some or all claims.
4. Response and amendment. The applicant must respond in writing, typically within a shortened statutory period of two or three months (six months maximum), addressing every ground of rejection — usually by amending claim language, arguing the examiner’s prior-art reading is wrong, or both. Failure to respond in time results in abandonment.
5. Allowance. Once the examiner is satisfied, the office issues a Notice of Allowance and sets an issue fee due within three months (a deadline that cannot be extended).
6. Issuance. After the issue fee is paid, the patent office grants the patent, and it enters force subject to ongoing maintenance-fee payments over its term.

This back-and-forth can run one round or many, and can take anywhere from about a year to several years depending on the technology area, examiner workload, and how many rounds of office actions the application draws.

Patent prosecution vs. patent litigation (the common confusion)

“Prosecution” reads, to most people outside patent law, like it should mean pursuing someone in court — it doesn’t. The two processes are genuinely different, not just different phases of the same one:

• Patent prosecution is administrative and collaborative: an applicant (or their counsel) works with a patent examiner at the patent office to get a patent granted. There is no adverse party; the examiner’s job is to test the application against the law, not to defeat the applicant.
• Patent litigation is adversarial and judicial: it happens after a patent has already been granted, in federal court (or an administrative tribunal such as the Patent Trial and Appeal Board for a validity challenge), between the patent owner and an alleged infringer or challenger. It is about enforcing or invalidating an existing patent right, not obtaining one.

A patent attorney or agent may specialize in one, the other, or both, but the skill sets differ: prosecution calls for technical fluency and precise claim drafting; litigation calls for advocacy and evidentiary practice. A university technology transfer office (TTO) will typically engage separate counsel, or a separate practice group within the same firm, for each.

Who actually handles prosecution at a university or research institution

Most TTOs do not prosecute patents in-house. Prosecution is technical, claim-drafting-intensive legal work, and the typical arrangement is:

• Outside patent counsel (a law firm or, at larger institutions, in-house patent attorneys) drafts, files, and prosecutes the application — corresponding directly with the examiner, drafting office-action responses, and negotiating claim language.
• The TTO manages the relationship and the decisions that carry cost and strategic weight: which inventions get filed at all, following an internal disclosure review of the underlying patent opportunity and its commercial potential; how aggressively to pursue claim scope versus narrow it to control cost; whether to file continuation applications to capture additional embodiments or claim scope discovered after the original filing; whether to pursue foreign counterpart filings (e.g., via the Patent Cooperation Treaty); and when to abandon a case that isn’t attracting licensee interest.
• The inventor typically stays involved as a technical resource — reviewing office-action responses for accuracy and, often, participating in an examiner interview alongside counsel — but is rarely the one drafting the legal response.

This division of labor is standard practice across research institutions in the AUTM (Association of University Technology Managers) community: the TTO functions as the client and portfolio manager, outside counsel as the technical drafter and USPTO-facing advocate. Prosecution cost is a real, recurring budget line for a TTO, which is why claim-scope and continuation-strategy decisions are made jointly with counsel rather than left entirely to the drafting attorney’s judgment.

Frequently asked questions

Does patent prosecution include litigation?

No. Prosecution ends when a patent is allowed and issued (or the application is abandoned). Litigation is a separate, later, court-based process that only arises if someone tries to enforce or invalidate an already-granted patent.

How long does patent prosecution take?

Widely variable — commonly one to several years from filing to issuance (or abandonment), depending on the examiner’s art unit, how many office actions are issued, and how the applicant responds to each one.

Who prosecutes a patent application?

A registered patent attorney or patent agent admitted to practice before the relevant patent office. At a university, this is typically outside counsel retained by the TTO rather than TTO staff themselves.

What happens if an application is rejected?

A rejection in an office action is not final in the everyday sense — it is an invitation to respond. The applicant amends claims, argues against the examiner’s prior-art position, or both, within the response deadline. Only after a genuine “final” rejection is maintained, or the applicant fails to respond at all, does the application go abandoned (short of appeal or a request for continued examination).

Related terms

See also CASRAI’s guides on provisional patent applications, patent novelty and invention-disclosure timing under 35 U.S.C. § 102, and open-source software licensing in technology transfer, plus the Technology Transfer & Innovation cluster hub.