The antiphospholipid antibody syndrome, also known as , is a disorder characterized by multiple different antibodies that are associated with both arterial and venous thrombosis (clots). There are three primary classes of antibodies associated with the antiphospholipid antibody syndrome: 1) anticardiolipin antibodies, 2) the lupus anticoagulant and 3) antibodies directed against specific molecules including a molecule known as beta-2-glycoprotein 1.