There's a similar situation for GPI / Paulson sample chips too. See, for example:

That one is listed under Paulson.

Also, for these 2 50 cent chips, one is listed under Paulson, and the other is listed under GPI:

It appears that a chip or plaque can be listed both places (see all the C.J.Sisk chips listed under both Sisk and under Paulson), so maybe BOTH is the answer to your original query?