Agreement Prosecution: Understanding What It Is and How It Works
Agreement prosecution, also known as prosecution history estoppel, is a legal doctrine that limits the scope of patent claims based on the arguments made during the patent application process. This doctrine is designed to prevent patent applicants from making arguments to obtain broader patent protection, only to later assert a more narrow interpretation of the claims in litigation.
To understand agreement prosecution, it is important to first understand the patent application process. When an inventor files a patent application, the patent examiner reviews the application and may reject some or all of the claims on various grounds, such as lack of novelty, obviousness, or written description. The inventor can respond to the examiner`s rejections by submitting arguments and evidence in support of the claims, or by amending the claims to overcome the rejections.
The arguments and amendments made during prosecution can have an impact on the scope of the claims that are ultimately allowed. In particular, the doctrine of agreement prosecution holds that an applicant who has narrowed the scope of a claim during prosecution cannot later assert a broader interpretation of that claim in litigation. The rationale for this doctrine is that an applicant who has argued for a narrow interpretation of a claim has essentially made a concession as to what the claim covers, and should not be allowed to later contradict that concession.
For example, suppose an inventor applies for a patent on a widget with a claim that reads « a widget with a red handle. » The patent examiner initially rejects the claim as obvious based on prior art showing widgets with handles of various colors. The inventor responds by arguing that the red handle provides an unexpected and non-obvious advantage over prior art widgets, and amends the claim to read « a widget with a red handle that provides an unexpected and non-obvious advantage. » The examiner allows the claim as amended.
Later, a competitor develops a widget with a green handle and is sued by the inventor for patent infringement. The competitor argues that the red handle limitation does not apply to their widget because it is an arbitrary and unnecessary limitation that the inventor added during prosecution to distinguish their widget from prior art. The competitor argues that the claim should be read to cover any widget with a handle that provides an unexpected and non-obvious advantage, regardless of the color.
Under the doctrine of agreement prosecution, the inventor would have a harder time asserting that the green-handled widget infringes their patent. The inventor has essentially conceded during prosecution that the red handle limitation was necessary to distinguish the widget from prior art, and cannot now take a broader interpretation of the claim that encompasses any color of handle.
In conclusion, agreement prosecution is an important legal doctrine that limits the scope of patent claims based on the arguments made during prosecution. Patent applicants should be aware of the potential impact of their arguments and amendments on the scope of their claims, and should work closely with their patent attorneys to ensure that they are not inadvertently limiting their patent protection. Similarly, patent litigators should be aware of the potential impact of prosecution history on claim interpretation and should carefully scrutinize the arguments made during prosecution to identify potential limitations on the scope of the claims.