Can preliminary amendments add new matter?

Preliminary amendments are a type of amendment that can be submitted to a patent application while it is still under examination. One of the key rules governing preliminary amendments is that they cannot introduce new matter into the application. New matter refers to information or claims that were not present in the original application when it was filed.

The rationale behind this restriction is to ensure that the integrity of the original application is maintained and that the scope of the application is defined at the time of filing. Allowing the introduction of new matter after the application has been filed could unfairly affect the examination process and potentially disadvantage third parties who may have relied on the original disclosure of the patent application.

Therefore, since preliminary amendments cannot add new matter, the correct understanding is that they are not allowed to introduce any additional content that was not previously disclosed in the application. This ensures clarity and fairness in the patenting process.