A surgical end effector, comprising: a first jaw; an anvil supported relative to said first jaw for selective movement relative to said first jaw between an open position and a closed position relative to each other; a firing member supported for axial movement within the surgical end effector between a beginning position and an ending position upon applications of firing and retraction motions thereto; a lock member (1730; 1740; 1750; 1760) that is movable between a locked configuration wherein said firing member is prevented from axial travel through the surgical end effector and an unlocked configuration wherein said firing member is axially advanceable through the surgical end effector; and a surgical staple cartridge comprising: a cartridge body sized to be seated within said first jaw, said cartridge body operably supporting a plurality of surgical staples arranged in staple lines therein; and a cam assembly movable between a starting position and an end position within said cartridge body, said cam assembly defining a central axis and comprising a plurality of cam features thereon wherein each said cam feature corresponds to at least one of said staple lines, said cam assembly further comprising at least one unlocking feature thereon laterally offset from said central axis and being configured to unlockingly engage a corresponding portion of said lock member (1730; 1740; 1750; 1760) when said cartridge body is seated within said first jaw and said cam assembly is in said starting position to thereby prevent said lock member (1730; 1740; 1750; 1760) from attaining said locked configuration when said anvil is moved to the closed position, wherein said anvil is configured to move said lock member (1730; 1740; 1750; 1760) in a first direction into locking engagement with said firing member when said anvil is moved to the closed position and wherein each said unlocking feature is configured to bias the corresponding portion of said lock member (1730; 1740; 1750; 1760) in a second direction that is opposite to the first direction. a first jaw; an anvil supported relative to said first jaw for selective movement relative to said first jaw between an open position and a closed position relative to each other; a firing member supported for axial movement within the surgical end effector between a beginning position and an ending position upon applications of firing and retraction motions thereto; a lock member (1730; 1740; 1750; 1760) that is movable between a locked configuration wherein said firing member is prevented from axial travel through the surgical end effector and an unlocked configuration wherein said firing member is axially advanceable through the surgical end effector; and a surgical staple cartridge comprising: a cartridge body sized to be seated within said first jaw, said cartridge body operably supporting a plurality of surgical staples arranged in staple lines therein; and a cam assembly movable between a starting position and an end position within said cartridge body, said cam assembly defining a central axis and comprising a plurality of cam features thereon wherein each said cam feature corresponds to at least one of said staple lines, said cam assembly further comprising at least one unlocking feature thereon laterally offset from said central axis and being configured to unlockingly engage a corresponding portion of said lock member (1730; 1740; 1750; 1760) when said cartridge body is seated within said first jaw and said cam assembly is in said starting position to thereby prevent said lock member (1730; 1740; 1750; 1760) from attaining said locked configuration when said anvil is moved to the closed position, wherein said anvil is configured to move said lock member (1730; 1740; 1750; 1760) in a first direction into locking engagement with said firing member when said anvil is moved to the closed position and wherein each said unlocking feature is configured to bias the corresponding portion of said lock member (1730; 1740; 1750; 1760) in a second direction that is opposite to the first direction. a cartridge body sized to be seated within said first jaw, said cartridge body operably supporting a plurality of surgical staples arranged in staple lines therein; and a cam assembly movable between a starting position and an end position within said cartridge body, said cam assembly defining a central axis and comprising a plurality of cam features thereon wherein each said cam feature corresponds to at least one of said staple lines, said cam assembly further comprising at least one unlocking feature thereon laterally offset from said central axis and being configured to unlockingly engage a corresponding portion of said lock member (1730; 1740; 1750; 1760) when said cartridge body is seated within said first jaw and said cam assembly is in said starting position to thereby prevent said lock member (1730; 1740; 1750; 1760) from attaining said locked configuration when said anvil is moved to the closed position, wherein said anvil is configured to move said lock member (1730; 1740; 1750; 1760) in a first direction into locking engagement with said firing member when said anvil is moved to the closed position and wherein each said unlocking feature is configured to bias the corresponding portion of said lock member (1730; 1740; 1750; 1760) in a second direction that is opposite to the first direction.