definiens: or shall mean an immunoglobulin ( Ig ) molecule, generally comprising fourpolypeptide chains, two heavy ( H ) chains and two light ( L ) chains, or an equivalent Ig homologue thereof(e.g ., a camelid nanobody, which comprises only a heavy chain, single domain antibodies ( dAbs ) which canbe either heavy or light chain ) ; including full length functional mutants, variants, or derivatives thereof(including but not limited to chimeric, veneered, humanized antibodies, fully human equivalents ( e.g. createdby guided selection or similar technology ), which retain the essential epitope binding features of an Igmolecule, and including dual specific, bispecific, multispecific, and dual variable domain immunoglobulins;Immunoglobulin molecules can be of any class ( e.g., IgG, IgE, IgM, IgD, IgA, and IgY ), or subclass ( e.g.,IgG1, IgG2, IgG3, IgG4, IgA1, and IgA2 ) and allotype . Also included within the meaning of the termAntibody is any ANTIBODY FRAGMENT