A stapling assembly, comprising: a first jaw; a second jaw movable relative to said first jaw; a staple cartridge comprising a plurality of staples, wherein each staple is comprised of a wire having a wire diameter; and an anvil configured to deform said staples, said anvil comprising: a tissue-engaging surface; and a pair of forming pockets (10500, 10600, 10700) defined in said tissue-engaging surface, wherein said pair of forming pockets is configured to deform corresponding legs of a said staple, and wherein said pair of forming pockets comprises: a proximal forming pocket (10510, 10610, 10710) comprising: a forming surface, wherein said forming surface comprises an entry zone comprising a first radius of curvature and an exit zone comprising a second radius of curvature; a pair of sidewalls (10513,10533,10613,10633,10713,10733) extending at an angle from said forming surface toward said tissue-engaging surface; and a groove (10515,10535,10615,10635,10715,10735) defined in said forming surface, wherein said groove comprises a diameter less than said wire diameter; and a distal forming pocket (10530,10630,10730) characterised in that said pair of forming pockets define a longitudinal pocket axis (10503,10603,10703) and wherein said pair of forming pockets are bilaterally symmetric with respect to said longitudinal pocket axis. a first jaw; a second jaw movable relative to said first jaw; a staple cartridge comprising a plurality of staples, wherein each staple is comprised of a wire having a wire diameter; and an anvil configured to deform said staples, said anvil comprising: a tissue-engaging surface; and a pair of forming pockets (10500, 10600, 10700) defined in said tissue-engaging surface, wherein said pair of forming pockets is configured to deform corresponding legs of a said staple, and wherein said pair of forming pockets comprises: a proximal forming pocket (10510, 10610, 10710) comprising: a forming surface, wherein said forming surface comprises an entry zone comprising a first radius of curvature and an exit zone comprising a second radius of curvature; a pair of sidewalls (10513,10533,10613,10633,10713,10733) extending at an angle from said forming surface toward said tissue-engaging surface; and a groove (10515,10535,10615,10635,10715,10735) defined in said forming surface, wherein said groove comprises a diameter less than said wire diameter; and a distal forming pocket (10530,10630,10730) characterised in that said pair of forming pockets define a longitudinal pocket axis (10503,10603,10703) and wherein said pair of forming pockets are bilaterally symmetric with respect to said longitudinal pocket axis. a tissue-engaging surface; and a pair of forming pockets (10500, 10600, 10700) defined in said tissue-engaging surface, wherein said pair of forming pockets is configured to deform corresponding legs of a said staple, and wherein said pair of forming pockets comprises: a proximal forming pocket (10510, 10610, 10710) comprising: a forming surface, wherein said forming surface comprises an entry zone comprising a first radius of curvature and an exit zone comprising a second radius of curvature; a pair of sidewalls (10513,10533,10613,10633,10713,10733) extending at an angle from said forming surface toward said tissue-engaging surface; and a groove (10515,10535,10615,10635,10715,10735) defined in said forming surface, wherein said groove comprises a diameter less than said wire diameter; and a distal forming pocket (10530,10630,10730) characterised in that said pair of forming pockets define a longitudinal pocket axis (10503,10603,10703) and wherein said pair of forming pockets are bilaterally symmetric with respect to said longitudinal pocket axis. a proximal forming pocket (10510, 10610, 10710) comprising: a forming surface, wherein said forming surface comprises an entry zone comprising a first radius of curvature and an exit zone comprising a second radius of curvature; a pair of sidewalls (10513,10533,10613,10633,10713,10733) extending at an angle from said forming surface toward said tissue-engaging surface; and a groove (10515,10535,10615,10635,10715,10735) defined in said forming surface, wherein said groove comprises a diameter less than said wire diameter; and a forming surface, wherein said forming surface comprises an entry zone comprising a first radius of curvature and an exit zone comprising a second radius of curvature; a pair of sidewalls (10513,10533,10613,10633,10713,10733) extending at an angle from said forming surface toward said tissue-engaging surface; and a groove (10515,10535,10615,10635,10715,10735) defined in said forming surface, wherein said groove comprises a diameter less than said wire diameter; and a distal forming pocket (10530,10630,10730) characterised in that said pair of forming pockets define a longitudinal pocket axis (10503,10603,10703) and wherein said pair of forming pockets are bilaterally symmetric with respect to said longitudinal pocket axis.