Hmm. Matrix aquired steel panthers 3 way back and converted it to steel panthers world at war. Meanwhile shrapnel games got steel panthers 1 and 2 and made their own improvements. Neither made money directly from the conversions but appear to have gotten rights to sell expansion campaigns / enhanced cd’s.
My recollection may be incomplete/faulty, but here is what I know -- whoever owned the Steel Panthers Intellectual Property (IP) at the time made deal(s) with both SPCAMO and Matrix Games.
Both development groups would get the source code to the Steel Panthers version they preferred (SP3 for Matrix, SP2 for SPCAMO), and both development groups would be allowed to redistribute whatever "remixed" games they made from the source code bases they got.
The proviso was, both development groups could not *profit* from the game; i.e. the games had to be free.
Matrix Games' solution to this was the "MegaCampaigns" concept -- a massive non-linear branching campaign with RPG elements (medals being awarded) and a situation map to show where you were. Instead of paying for the game, you paid for the MegaCampaign.
SPCAMO's solution when they went from DOS to Windows versions was to make an "Enhanced Version". The free version's maximum resolution was like 800x600, but if you wanted 1600x1200 resolution, you had to pay for the Shrapnel CD. Additionally, a better map editor; ScenHack Utility, CampaignHack Utility, and encrypted tournament play mode were also part of Enhanced. Shrapnel kept adding new features to the Enhanced version over the years.
I don’t think your recollection could get any more complete than that ! ;)