The function of Ensembl gene identifier ENSG00000170956 (CEACAM3, CEA cell adhesion molecule 3) is as follows. Major granulocyte receptor mediating recognition and efficient opsonin-independent phagocytosis of CEACAM-binding microorganisms, including Neissiria, Moxarella and Haemophilus species, thus playing an important role in the clearance of pathogens by the innate immune system. Responsible for RAC1 stimulation in the course of pathogen phagocytosis. {ECO:0000269|PubMed:12864848, ECO:0000269|PubMed:14707113}.