By: Emma Saffman

On March 16, 2013 U.S. patent law will shift from first-to-invent to first-inventor-to-file. This means that the first to file a patent application will (with some exceptions) be the winner of a patent, regardless of who was the first to invent.
The effective filing date for a patent application will become all-important in the race to patent.

Existing U.S. law will continue to apply to applications effectively filed before March 16, 2013. Many innovators are therefore rushing to file new patent applications before March 16, to ensure that their applications continue to fall under existing law. However, great care must be taken to avoid certain pitfalls.

If both the priority date and the U.S. filing date (i.e., the filing date of a U.S. nonprovisional application or the filing date of a PCT application designating the U.S.) are before March 16, 2013, then existing law (first-to-invent) will apply. In contrast, if both the priority date and the U.S. filing date are after March 16, 2013, then the new AIA law (first-inventor-to-file) applies.

The situation quickly becomes complicated if the first priority date is before March 16, 2013, and the U.S. filing date is after March 16, 2013. Which law will apply? The answer depends on the effective filing dates of the claims in the U.S. application. If all claims in the U.S. application are entitled to the pre-March 16 priority date, then existing law will apply. However, AIA law will apply to applications having even a single claim with an effective filing date on or after March 16, 2013, even if that claim is later cancelled. Further, in this situation AIA law will apply to all claims in the application, even claims that would otherwise have been entitled to the pre-March 16 priority date.

It’s even more complicated if you consider that, for a claim to be entitled to the priority date, the priority application must meet all of the written description and enablement requirements. If new subject matter added after March 16, 2013 is required to meet these requirements, then a claim will not be entitled to the priority date, and will fall under AIA law.

Great care must be taken when crafting claims for a U.S. application where new subject matter has been added after March 16, 2013, especially if an applicant wishes existing law to apply to pre-March 16 subject matter. To avoid falling under AIA law, claims covering new subject matter (subject matter added to the application on or after March 16, 2013) should not be added to the U.S. application. Instead, file a continuation application and claim new subject matter there. This will maximize the number of claims considered under existing law by avoiding “contamination” by claims having a post-March 16 effective date.

Care should also be taken when drafting claims for a PCT application, if subsequent national entry in the U.S. is planned. The claims in the PCT application are subject to the same rules outlined above and will dictate which law applies to U.S. national entry applications.