Patent Express Logo
Contact us
Toll-free: (877)-794-9511
Ask a question
Ask a question
See Questions and Answers
See Questions and Answers
Discover more services
Discover more services
Search for Patent Questions:

PCT priority date

Posted by Anonymous . updated on 2/26/2009
Suppose that today (1/31/08) I want to file a PCT application based on a CIP (filed 3/1/07) of a US application (filed 10/1/05 and published 10/1/06) claiming priority to a provisional application (filed 3/1/05).  Based on my understanding, I can only claim priority to the CIP because the other applications were filed more than a year ago.  Is this correct?  If so, can the US application filed 10/1/05 be used as prior art against any national stage application based on the PCT application?  Thanks for your help.
Answers (2)
You are correct. You are entitled to claim priority from applications filed at the most 12 months before the filing date of your application. Thus, it is now too late to claim priority from the original US application. Moreover, you can only claim priority from the first application for a given subject-matter so that if your PCT application contains subject-matter which was present in the published US application, your priority claim will not be valid. Thus, not only the publication of the US application but any other prior art published until the date of filing of the PCT application qualifies as prior art for the purposes of novelty and obviousness. I am savvy with the European procedure but I believe this will be the same in other national/regional offices because it is based on principles included in the Paris Convention, which covers most of the world.

Of course, this only applies to the subject-matter which was included in the first US application. Any subject-matter added in the CIP application will enjoy a valid priorrity claim if you file a PCT application. Still the contents of the published US application will be citable for the purposes of inventive step against said added subject-matter.

I hope this helps
Thanks alconada.  This is helpful information.
Related Questions
In International patents    -  posted on 4/24/2009
I am currently in business with a US-European company. I have completed a ''contract'' with them where they have bought a shipment of goods. My problem is that a large portion of the payment is due next year...   Read MoreAnswer this question
In International patents    -  posted on 11/28/2008
After getting patent grant from EPO, the patent is entered into the designated countries in EPO region. Will the patent number at designated countries remain same as EPO or different number?   Read MoreAnswer this question
In International patents    -  posted on 5/21/2007
what are the differences between the procedure regarding grant of patent in u.s, u.k and india?   Read MoreAnswer this question
In International patents    -  posted on 11/24/2006
Dear Sirs: If a patent is issued in Italy for a specific scientific test/application, does that patent apply in the US? A scientist in Italy says he has patented a technique to determine the age of wood in a...   Read MoreAnswer this question
In International patents    -  posted on 11/24/2002
What are the adbantage and disadvantage of the priority rights in the US and European law?   Read MoreAnswer this question
Why Patent Express?
  • Patent Express is the fastest and easiest way for an individual inventor to file a U.S. Patent or Trademark Application.
  • Patent Express fills the gap for those who cannot afford a U.S. patent attorney or agent, but want to have their patent drafted and issued.
  • Patent Express is backed by a 100% money back guarantee.
Save 95% more in register a trademark
Patent Express Services is a website of Raj Abhyanker, a professional U.S. Patent Law firm, see: for more. All non-do-it-yourself related services advertised on this site are supervised and managed by a U.S. patent attorney.

© All rights reserved. Disclaimer: The information provided in this site is not legal advice, but general information on legal issues commonly encountered. Please note that your access to and use of is subject to additional terms and conditions. 03-30-2015