Determine the Process ID of the Client Process com

Question

In a COM RPC Model, if the Server is running on a separate process, is it possible to know, the Process ID of the client Process communicating with the Server?

Use Case

I have an Out Process RPC Server which can receive request from one or more client process. Occasionally, the server needs to know the Client Process to write data back to the client address space using Write Process Memory.

Also Note, the API Signatures, the way the buffer is getting allocated and the APIs are getting called are beyond my control.