Surgical stapler anvil with directionally biased staple pockets

An end effector for a surgical stapling apparatus includes a cartridge assembly and an anvil assembly. The cartridge assembly supports staples. Each staple includes a backspan, a first leg, and a second leg. The first and second legs extend from the backspan. The anvil assembly is coupled to the cartridge assembly. The anvil assembly includes an anvil having opposed side surfaces. The anvil defines a knife slot and biased staple-forming pockets disposed between the opposed side surfaces of the anvil. Each biased staple-forming pocket is positioned to form the first and second legs of a respective staple on one side of the backspan of the respective staple. The one side of the backspan is positioned toward the knife slot of the anvil relative to the opposed side surfaces of the anvil.