Unveiling The Impact Of Optional Language "May" In A Patent Application

• Published date: 18 August 2023
• Subject Matter: Intellectual Property, Patent
• Law Firm: NovoTech Patent Firm
• Author: Mr Babak Akhlaghi

A Brief Legal History: Understanding Reissue Patents

Patent owners have the option to seek a broader scope of coverage for their invention by filing a continuation application with the United States Patent and Trademark Office while their original application is still pending. This allows them to include claims that extend to the full scope of the subject matter described in the original specification. However, once a patent is granted, changes to the scope of the claims can only be made through a vehicle call "reissue," which is subject to additional statutory limitations.

One of these limitations is the requirement that the reissue claims must be directed to the same invention as the original patent. This is known as the "original patent" requirement. The standard for satisfying this requirement is established in the U.S. Industrial Chemicals, Inc. v. Carbide & Carbon Chemicals, Corp., 315 U.S. 668 (1942). In this Supreme Court case, the original patent included a specification that stated water improved the efficiency of a certain reaction. However, after the patent was issued, the patent owner discovered that water was not actually necessary for the most efficient reaction. A reissue patent was obtained with a substitute specification and new claims, indicating that the reaction could take place with or without added water.

The Supreme Court ruled that for a reissue patent to be valid, it must fully describe and claim the same invention intended to be secured by the original patent. It must be clear from the face of the reissue patent that what is covered by it was intended to be covered and secured by the original patent. In this case, because the original patent treated the introduction of water as a necessary step, its absence in the reissue claims rendered those claims invalid. The Supreme Court also clarified that simply suggesting or indicating a new invention in the original patent specification does not automatically meet the requirements of a reissue claim. The Supreme Court further explained that a reissue claim does not meet the "original patent" requirement merely because the newly claimed invention could have been claimed in the original patent and was supported by the original specification.

In summary, applicants have the ability to expand the scope of their patent claims while their application is pending, but once a patent is granted, changes to the claims can only be made through a reissue patent, which must satisfy the "original...