An end effector of a surgical instrument configurable in an open configuration and a clamped configuration, comprising: a jaw comprising a cartridge channel; a staple cartridge seatable in said cartridge channel, comprising: a proximal end ; a distal end; a deck extending between said proximal end and said distal end, wherein said deck is configured to support the tissue of a patient; a longitudinal slot defined in said deck extending from said proximal end toward said distal end; staple cavities arranged in longitudinal rows; staples removably stored in said staple cavities; retention features configured to releasably hold said staple cartridge in said channel; and a projection extending above said deck; and an anvil , comprising: staple forming surfaces configured to deform said staples when said staples are ejected from said staple cartridge during a staple firing stroke; a proximal end; and a distal end; and characterized by a cam extending from said proximal end configured to contact said projection when said end effector is in said clamped configuration to seat said staple cartridge in said cartridge channel if said staple cartridge is not fully seated in said cartridge channel when said end effector is moved into said clamped configuration. a jaw comprising a cartridge channel; a staple cartridge seatable in said cartridge channel, comprising: a proximal end ; a distal end; a deck extending between said proximal end and said distal end, wherein said deck is configured to support the tissue of a patient; a longitudinal slot defined in said deck extending from said proximal end toward said distal end; staple cavities arranged in longitudinal rows; staples removably stored in said staple cavities; retention features configured to releasably hold said staple cartridge in said channel; and a projection extending above said deck; and a proximal end ; a distal end; a deck extending between said proximal end and said distal end, wherein said deck is configured to support the tissue of a patient; a longitudinal slot defined in said deck extending from said proximal end toward said distal end; staple cavities arranged in longitudinal rows; staples removably stored in said staple cavities; retention features configured to releasably hold said staple cartridge in said channel; and a projection extending above said deck; and an anvil , comprising: staple forming surfaces configured to deform said staples when said staples are ejected from said staple cartridge during a staple firing stroke; a proximal end; and a distal end; and characterized by a cam extending from said proximal end configured to contact said projection when said end effector is in said clamped configuration to seat said staple cartridge in said cartridge channel if said staple cartridge is not fully seated in said cartridge channel when said end effector is moved into said clamped configuration. staple forming surfaces configured to deform said staples when said staples are ejected from said staple cartridge during a staple firing stroke; a proximal end; and a distal end; and characterized by a cam extending from said proximal end configured to contact said projection when said end effector is in said clamped configuration to seat said staple cartridge in said cartridge channel if said staple cartridge is not fully seated in said cartridge channel when said end effector is moved into said clamped configuration. <EOS>