Provided is a humanized Type II anti-CD20 antigen binding molecule comprising a heavy chain with a specified sequence, including a variant thereof, wherein said variant comprises one or more substitutions selected from 516A, A24V, A28T, S30T, M34I, N35S and Y91L, E1 Q, G9A, Li 1V, V12K, G16S, L20V, A24V, F27Y, T28A, S30T, N35S, V48M and Y91L, the residue numbering according to the Kabat system, wherein said antigen binding molecule induces higher levels of apoptosis when incubated with CD20-positive human cells relative to a control under identical conditions using the C2B8 chimeric IgG1 antibody with an identical sequence to rituximab. Further provided are polynucleotides coding for the antibodies.
CD20 antibodies with increased Fc receptor binding affinity and effector function