This contribution proposes several simplification methods for OBMC. The first method is to remove the ‘obmc_flag’ syntax which is signalled in every CU. Encoder would save memory associated with OBMC on/off decision. The second method is to disable a sub-block OBMC according to the result of a template matching based OBMC. If a template matching based OBMC has not been performed on any CU boundary block, a sub-block OBMC is also not applied for the CU. The third method is to disable OBMC in coding blocks with large block size. When the block size cbW * cbH is greater than or equal to 32(ECM-5.0) and cbW and cbH is less than 128 (additional restriction), OBMC is applied. On top of ECM-5.0, simulation results of the proposed method are reported as below: