The present invention relates to a novel divalent antibody capable of binding specifically to the human c-Met receptor and/or capable of specifically inhibiting the tyrosine kinase activity of said receptor, preferably both in a ligand-dependent and in a ligand-independent manner as well as the amino acid and nucleic acid sequences coding for said antibody. More preferably said antibody comprises a modified hinge region and exhibits an improved antagonistic activity. More particularly, the antibody according to the invention is capable of inhibiting the c-Met dimerization. The invention likewise comprises the use of said antibody as a medicament for the prophylactic and/or therapeutic treatment of cancers, preferably for cancer characterized by a ligand- independent activation of c-Met,or any pathology connected with the over expression of said receptor as well as in processes or kits for diagnosis of illnesses connected with the over-expression of c-Met. The invention finally comprises products and/or compositions comprising such an antibody in combination with other antibodies and/or chemical compounds directed against other growth factors involved in tumor progression or metastasis and/or compounds and/or anti-cancer agents or agents conjugated with toxins and their use for the prevention and/or the treatment of certain cancers.La présente invention concerne un nouvel anticorps bivalent, capable de se lier spécifiquement au récepteur c-Met humain et/ou capable dinhiber spécifiquement lactivité de tyrosine kinase dudit récepteur, de préférence à la fois de manière dépendante du ligand et de manière indépendante du ligand, ainsi que les séquences des acides aminés et dacide nucléique codant ledit anticorps. Mieux encore, ledit anticorps comprend une région charnière modifiée et présente une activité antagoniste améliorée. Plus particulièrement, lanticorps selon linvention est capable dinhiber la dimérisation du c-Met. Linvention concerne également, lutilisation dud
