Written description

Abstract

A brief summary (300 words or fewer) that appears at the top of every patent. The abstract describes what the invention does in general terms. Legally, it has almost no weight — courts use the claims to determine what a patent covers, not the abstract. The abstract is useful mainly for quickly scanning patents during a prior art search.

Anticipation

A legal standard for rejecting a patent claim. If every element of a claim was already disclosed in a single prior art reference — in a patent, article, or product — the claim is "anticipated" and cannot be patented. Anticipation requires a single source to contain every element; if you need two sources, it's an obviousness argument, not anticipation.

Appeal

A request to have a patent examiner's rejection reviewed by a higher authority. After receiving multiple rejections, an applicant can appeal to the Patent Trial and Appeal Board (PTAB) within the USPTO, and from there to federal court. Appeals are expensive and slow, but sometimes necessary when an examiner applies the law incorrectly.

Art unit

A group of patent examiners at the USPTO who specialize in a particular technology area. Each application is assigned to the art unit whose examiners are trained in the relevant field. The art unit assignment matters because examiner expertise — and rejection rates — vary significantly across technology areas.

Assignee

The legal owner of a patent, who may or may not be the inventor. When an employee invents something in the course of their employment, most companies require inventors to assign patent rights to the employer. The assignee appears on the patent document and has the right to license or enforce the patent.

Basis for rejection

The specific legal grounds a patent examiner cites when refusing to allow a claim. Common bases include lack of novelty (35 USC § 102), obviousness (35 USC § 103), failure to fully describe the invention (35 USC § 112), and unpatentable subject matter (35 USC § 101). An office action will state the basis for each rejection, and applicants must address each one in their response.