Methods, systems, and devices for wireless communication are described. In multi-user (MU) multiple-input multiple-output (MIMO) wireless communications systems, a base station may perform signaling to indicate information related to ports assigned to one or more UEs. The base station may also signal information regarding ports shared with other UEs, which the UE may use when performing channel estimation. In some examples, the base station may signal a number of ports used per sub-band to the UE or a number of demodulation reference signal (DMRS) ports used by the UE. The base station may signal a sub-set of a total number of ports that are shared by other UEs overlapping with the resource allocation of the UE. The signaling may indicate a number of combs used by the base station in the resource allocation for the UE.