Robert Cooper Grier,
Case v. Brown — Opinion of the Court
“ But as this claim was not broad enough to cover the improvement described in defendant's patent, the plaintiff surrendered his, and had it reissued with a more expanded claim. It is for the infringement of this reissued patent that the action is brought.We have had occasion to remark, in a late case, [2] on this new art of expanding patents for machines into patents for 'a mode of operation,' a function, a principle, an effect or result, so that by an equivocal use of the term 'equivalent,' a patentee of an improved machine may suppress all further improvements. ”
