Surgical stapler anvil with nested staple forming pockets

In a staple forming anvil of a surgical stapler, the anvil having an upper surface defining a plurality of staple forming pockets in parallel rows, each said pocket comprising:

• first and second leg forming cups each including a descending leg-receiving portion and an ascending leg-clinching portion, said leg-clinching portions being adjacent and said leg-receiving portions being spaced apart, each cup comprising:
• a concave arcuate clinching surface extending between said leg-receiving portion and said leg clinching portion parallel to a longitudinal axis of;
• anvil;
• and
• laterally spaced apart guide surfaces extending upwardly and outwardly from said clinching surface, a laterally outward-most portion of said guide surfaces being substantially planar,
• wherein pockets in the parallel rows are staggered so that a leg-receiving portion of a pocket in one row is aligned with a leg-clinching portion of a pocket in an adjacent row, the guide surfaces of adjacent rows intersecting to define a ridge separating the cups of one row from the cups of an adjacent row, the improvement comprising:
• the leg-receiving portions of at least one row of pockets having a lateral width that is at least 25% greater than a lateral width of the leg-clinching portions of pockets in the same row, the increased lateral width of said leg-receiving portions being taken from the leg-clinching portions of cups in an adjacent row.