Heart Guard Corp. $("$HGC$")$ had their patent lawyer prepare a U$.$S$.$ patent application for a defibrillator $($a device that re$-$starts the heart of a patient suffering from a heart attack$).$ The lawyer filed the patent application, using ordinary open$-$ended claiming $($using the word "comprising"$),$ and a valid, enforceable U$.$S$.$ patent later issued with that language. Shortly after issuance, a competitor, Ticker Fixer Inc. $("$TFI$",$ without knowledie of the patent, produced and sold a product in the U$.$S$.$ that contained a nonobvious add$-$on $-$ type improvement. TFI later obtained an ISSUED U$.$S$.$ PATENT for the improved device. On the basis of these facts, if HGC sues, what will the likely result be regarding whether or not TFI's device is legally viewed as an infringement of HGC$\text{'}$s patent?