PC-86-DOS
os2museum.com
os2museum.com
EDIT: It does seem like the actual programmer, Tim Patterson, did better out of it. After working for SCP, he worked a couple stints at Microsoft, and wrote and sold MSX-DOS for the MSX machines as well.
>Paul Allen negotiated an agreement with SCP owner Rod Brock in January, implying that Microsoft had a whole stable of customers eager to run 86-DOS. The deal would essentially allow Microsoft to act as middleman — or, if you like, retailer — in these transactions. For each customer to whom they sold a license for 86-DOS, they would pay SCP $10,000, or $15,000 if the license also included the source code. [...] One clause buried in the contract might have raised a red flag: “Nothing in this licensing agreement shall require Microsoft to identify its customer to Seattle Computer Products.” Brock later said, “That seemed strange to us, but we agreed to go along.” In reality, of course, Microsoft had no stable of eager licensees. They had just one, the biggest fish of all: IBM. Microsoft sold just one license under the agreement, acquiring IBM’s operating system for them complete with source for just $25,000.
Of course, history is full of "what ifs" which can drive one crazy.
> After Microsoft objected to Brock's "exaggerated interpretation" of the agreement and informed Brock that his license was nontransferable, Brock sued for US$60 million. The ensuing lawsuit was highly technical and grew to fill hundreds of pages in the months leading up to trial. The trial began at the end of 1986 and lasted three weeks. An out-of-court settlement was reached while the jury was deliberating. Microsoft paid SCP US$925,000 and reclaimed its license for DOS.
Wow! $60M would have killed the 80's version of MicroSoft.
EDIT: Also, clearly the "$60M" was not a number conjured out of thin air. That's basically Microsoft's market cap at IPO. Suppose Brock was fundamentally trying to make the point that MS's entire financial success had been built off of this deal.