Putative inactive caspase (PubMed:9857046). In the germline, binds caspase ced-3 zymogen and prevents ced-3 autoactivation. Does not affect the caspase activity of mature ced-3 and ced-4-mediated mature ced-3 activation (PubMed:19575016). Negatively regulates germline apoptosis by inhibiting autocleavage of caspase ced-3 (PubMed:19575016). Involved in fertility (PubMed:19575016). Putative inactive caspase (PubMed:9857046). Dispensable for the inhibition of germline apoptosis (PubMed:19575016). Interacts with ced-3 (via large subunit p17 or small subunit p13); the interaction inhibits ced-3 autoactivation. Specifically expressed in the hermaphrodite germline. Cleavage by csp-1 isoform b or ced-3 removes the propeptide and generates subunit p31 in vitro. An additional cleavage at Asp-149 generates the 2 subunits p17 and p14 but this cleavage appears to be less efficient. Survival of touch neurons and several pharyngeal cells is not affected during development. In a ced-3 n2427 or ced-3 n2427 and cps-3 n4872 mutant background, no extra pharyngeal cells caused by impaired apoptosis are produced. In a csp-3 n4872, csp-1 n4967 and ced-3 n3692 mutant background, pharyngeal cells, that are normally fated to die, survive and 16 percent of animals have still 1 or more cell corpses that are morphologically apoptotic and are internalized by engulfing cells. In addition, apoptosis of the male linker cell occurs normally. Belongs to the peptidase C14A family. Although the active site residues Cys and His are conserved, appears to lack catalytic activity in vitro. This is probably due to the active site pentapeptide VCCRG being highly divergent from the canonical active site pentapeptide QAC[RQG]G present in catalytically active caspases.