Catalytic component of the Integrator complex, a complex involved in the small nuclear RNAs (snRNA) U1 and U2 transcription and in their 3'-box-dependent processing. Mediates the snRNAs 3' cleavage (By similarity). The HXHXDH motif is essential for the endoribonuclease activity of the CPSF complex. Belongs to the metallo-beta-lactamase superfamily. RNA-metabolizing metallo-beta-lactamase-like family. INTS11 subfamily.