Apparatus for processing multisheet or manifold business forms assemblies comprises at least one pair of rotary slitters, a male crimping die or punch associated with one of the slitting blades of the pair for rotation therewith, and a female crimping die or punch receptacle associated with the other of the slitting blades for rotation therewith. Upon rotation of the slitters and their associated crimping dies, the manifold assembly is concurrently slit and crimped to produce locks or paper staples in the body of the assembly. These paper staples effectively hold the various sheets of the assembly in registration or alignment during subsequent processing, but readily permit separation of the various sheets of the assembly when desired.