After delivery, it is not possible to extend the scope of his patent, under penalty of nullity (L613-25 CPI, d)): " The patent is declared invalid by a court decision ... if, after limitation, the scope of the protection conferred by the patent has been increased ».
Of course, under this assumption the limitation of the article L613-24 CPI will not have been a real limitation ...
Subject not initially covered by the claims
In order to demonstrate an extension of scope, it is sufficient to show that the new claims cover a new element that was initially outside the scope of the patent.
In other words, if a third party becomes an infringer, simply because of the limitation, the limitation must be prohibited to the visa of the article L613-25 CPI, d).
Addition of new claims when limiting
Adding a claim independent not including all the teachings of at least one independent claim issued is clearly an extension of scope (Paris District Court, 3rd Division, 1st Sect., May 21, 2015, RG No. 2014/02007).
If the addition relates to claims dependent, this is more questionable: in my opinion, this addition is not an extension if and only if the claims on which these new claims depend are declared valid by the court / court.
Adding a technical effect to the claims
The fact of adding a technical effect to a claim does not seem likely to increase the scope of this claim (eg " so as to create a moment of recall that opposes the sinking of the suspension") (Court of Appeal of Lyon, 1st c. civ., sect. A, July 13, 2011, RG No. 2009/02302).
Indeed, this addition only refers to the result of technical characteristics, and not a technical characteristic as such (Court of Appeal of Lyon, 1st c. civ., sect. A, July 13, 2011, RG No. 2009/02302).