Bullet maker SinterFire Inc. has added Automated Precision Technology LLC (APT) as a defendant in a suit accusing International Cartridge Corp (ICC) of gaining an unfair competitive edge by infringing patents and trademarks for frangible bullet designs. APT, a lead-free weapons operator, sold in bulk infringing ammunition it had purchased from ICC, a move that fraudulently led the public to believe it was buying SinterFire bullets, according to an amended complaint lodged Thursday in the U.S. District Court for the Eastern District of Virginia. The suit asserts four counts of patent infringement and a fifth claim for trade dress infringement and unfair competition. SinterFire seeks injunctive relief, disgorgement, destruction of ads promoting infringing products, and trebled damages with interest, costs and fees. SinterFire is represented by Finnegan.