Can preliminary amendments add new matter?

Preliminary amendments in a patent application serve a specific purpose, primarily to make adjustments or corrections to the application before it is examined. The rules governing these amendments are quite strict regarding the introduction of new matter. New matter refers to any information or content that was not originally included in the patent application at the time of its filing.

The United States Patent and Trademark Office (USPTO) prohibits the addition of new matter through preliminary amendments. This is to maintain the integrity of the original filing date and to ensure that the claims and disclosures remain consistent with what was originally submitted. Allowing new matter could potentially confuse the examination process and disadvantage parties who may have been relying on the original disclosure.

Thus, the prohibition against adding new matter through preliminary amendments is a key aspect of patent law, ensuring that the content of the patent remains stable and that changes do not introduce issues of fairness or clarity during the examination process.