Right. And the key word in that key sentence is substantive.

See the link below for further discussion:

http://www.law.cornell.edu/uscode/text/35/252

" . . . in so far as the claims of the original and reissued patents are substantially identical, such surrender shall not affect any action then pending nor abate any cause of action then existing, and the reissued patent, to the extent that its claims are substantially identical with the original patent, shall constitute a continuation thereof and have effect continuously from the date of the original patent." (emphasis added)