Provides anti b7-h4 Antibodies and Immunoconjugates and their methods of use.Claim 1: isolated an Antibody that binds to b7-h4 Antibody, which comprises: (a) (i) - HVR H3 comprising the amino acid sequence of SEQ ID no. 128, (ii) HVR - L3 comprising the amino acid sequence of SEQ ID no. 129 and (iii) - HVR H2 comprising the sequence of amino u00e1 In SEQ ID no. 40; or (b) (i) - HVR H3 comprising the amino acid sequence of SEQ ID no. 41(ii) HVR - L3 comprising the amino acid sequence of SEQ ID no. 129 HVR H2 and (iii) comprising the amino acid sequence of SEQ ID no. 40.Claim 21: an Antibody biepit u00f3pico comprising a First and a Second semianticuerpo semianticuerpo, where the first Unit comprises a First semianticuerpo VH / VL which connects a First epitope of b7-h4 and where the second Unit comprises a Second semianticuerpo VH / VL Q EU joins a Second epitope of b7-h4.Claim: The inmunoconjugado 50 according to the claim or the claim 48 49 which has the formula AB - (L - d) u209a, where: (a) AB is the Antibody according to any one of claims 1 to 44; (b) l is a Linker; (c) D is the agent cytotoxic; and (d) P varies from 1 - 8.Claim 76: a method of treating an individual having a cancer b7-h4 positive, that includes administering to the individual an effective amount of inmunoconjugado according to claim 47 to 72.Claim 87: a method for the detection of Human b7-h4 in a Biological Sample which comprises contacting the Biological Sample with the Antibody anti b7-h4 according to any one of claims 1 to 44 and 84 to 86 in conditions that allow the binding of Antibody anti B7 - H 4 with a natural Human b7-h4 and detect if there is a complex between the Antibody and an anti b7-h4 b7-h4In the natural Human Biological sample.Proporciona anticuerpos de anti-B7-H4 e inmunoconjugados y sus métodos de uso. Reivindicación 1: Un anticuerpo aislado que se une con B7-H4, en donde el anticuerpo comprende: (a) (i) HVR-H3 que comprende la secuencia de aminoácidos de SEQ ID Nº 128, (