Patent application

A patent application is a request pending at a patent office for the grant of a patent for the invention described and claimed by that application. An application consists of a description of the invention (the patent specification), together with official forms and correspondence relating to the application. The term patent application is also used to refer to the process of applying for a patent, or to the patent specification itself (i.e. the content of the document filed with a view to initiating the process of applying for a patent ).

In order to obtain the grant of a patent, a person, either legal or natural, must file an application at a patent office with the jurisdiction to grant a patent in the geographic area over which coverage is required. This will often be a national patent office but may be a regional body, such as the European Patent Office. Once the patent specification complies with the laws of the office concerned, a patent may be granted for the invention described and claimed by the specification.

The process of "negotiating" or "arguing" with a patent office for the grant of a patent, and interaction with a patent office with regard to a patent after its grant, is known as patent prosecution. Patent prosecution is distinct from patent litigation which relates to legal proceedings for infringement of a patent after it is granted.

As pointed out by Peter Prescott QC, the expression "patent application" is ambiguous. It can bear two different meanings:

The first of those – the request for a legal privilege to which you will be entitled if your application be well founded – is an institutional fact, and is temporal by its very nature. It ceases to exist as soon as your application is withdrawn, is refused, or is granted. The second of those, the informational content of the document as filed (or in other, prosaic words, the piece of paper), is a historical fact that never goes away, no matter what the Patent Office does, or anyone else does. It exists in perpetuity. The expression "application" is often employed without being conscious of its ambiguity. The expression is capable of misleading even experienced professionals.

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Wikipedia