In a PCT filing, is there any estoppel effect of arguments presented during the international phase (under art 19 or art 34) on national phase filings?

  • What country are you interested in? Since this is a matter of national law and practice, the answer will differ by country. – Maca Feb 8 at 8:44
  • @Maca if you find a single example where the answer is yes, the answer to the whole question is yes. – DonQuiKong Feb 8 at 9:52
  • @Maca - For example, United States and in say two scenarios a) US patent is already issued and b) US patent is still under examination – iktaara Feb 9 at 5:02

Under Art 19 and 34 of WIPO, for an amendment, a statement for basis of amendment is required.

I feel, if amendment is made to specification and/or drawing than the section of specification and the drawing prior to amendment and statements thereto may cause estoppel action because the later version is chosen as the best mode of practice and applicant is supposed to frame claims for protection of best mode of practice.

For claims it's a bit different. USPTO allows reinstatement of withdrawn claims and canceled claims (with new serial number). So, prima facie, amendment of claims and arguments thereto need not have estoppel effect. But, if your claim includes limitations as to what your invention can not do, then it surely will have estoppel effect. Because, if it is explicitly claimed that a certain invention can not do a function A and afterwards an amendment is done to claim list to include that the invention can perform the function A, that will face estoppel.

  • From WIPO web site - "1.05. What is a statement accompanying an amendment? Any amendment MAY BE accompanied by a brief statement by the applicant explaining the amendment and indicating any impact it might have on the description and the drawings." I capitalized the MAY BE. The statement is not required. – George White Feb 16 at 21:07
  • Claims that are withdrawn can be brought back - that is why they were withdrawn instead of cancelled. A new claim can be added that has the identical text of a canceled claim. It may be objected to as being outside the scope of an election made in response to a restriction requirement. – George White Feb 16 at 21:11

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