SLP2000: This depends on licence agreement between TSR and SSI.
I have noticed that in US law in some cases after licence expires, all rights are coming back to the copyright holder. Don't know why is that, because it's slighty different than in Polish law.
So I'd bet that his is the case of agreement. And it is possible, that after D&D licence for SSI expired, all rights went to TSR/WOTC/Hasbro.
captainvideo111: It pains me to say this, as I am a GOG fan and customer, but the new web site has a few bugs still, and arrgghhh... I have to full-screen my browser window (IE8) to see all the comment text, which was never a problem on the old site. And I tried replying to this once before, and got the "blue globe of death" when the site dropped me for some unknown reason.
Anyhow... You have to remember the TSR-to-SSI license was signed more than 20 years ago, when PC gaming was still in its infancy, and the contract language they used for expiration and transfer rights was probably a lot different than what you would expect them to use today. Even in the USA no one seems to know for sure what the deal is. Ubisoft is claiming the rights, and that's what matters.
It affects a lot of SSI titles for which there is interest in reprints. The Gold Box engine spawned 12 titles (10 AD&D + 2 Buck Rogers). Hillsfar was another AD&D title in a "Gold Box" package but used its own engine. The Dark Sun engine spawned seven titles (2 Dark Sun, 2 Ravenloft, Menzoberranzan, Al-Qadim and Jorune: Alien Logic). There were three more dungeon crawlers using the 3D Eye of the Beholder engine. I've lost count of how many used the Panzer General/Steel Panthers engine, but it was quite a few.
I can comment on some of the Gold Box Games. I big in gaming circles around that time.
v1 Gold Box Engine (classic). The copy protection was a code, picked from matching an Elvish and Dwarvish rune on a wheel. It was easier to unpack the PKpacked EXE and look for strings than it was to match those stinking runes (granted I was 15 at the time, paying attention wasn't a strong point)
Pool of Radience
Curse of the Azure Bonds
Secret of the Silver Blades
Pools of Darkness
There was a Ravenloft game or two and another - ah - Buck Rogers - thanks! I don't fully remember
Hillsfar Engine...
Hillsfar (more of a action/platformer than a Gold Box Game) It was meant to be played in the interim between Pools of Radience and Curse of the Azure Bonds. The most annoying thing was that you had to complete an action sequence (jumping hay bales, fences and puddles) before you could enter the game or leave and save the game. I cannot remember what the copy protection was, but it was probably a doc check (what is word 7 of line 2 on page 1) before entering upon saving the game. Dasterdly programmers.
v2 Gold Box Engine (much improved graphics - I think VGA, previous was EGA, Beholder size fixed (2x2) - you could backstab beholders in the v1 engine as they were rendered with only one tile due to a reading error, I guess)
Dark Queen of Krynn
Something Treasure of Krynn
There was also Unlimited Adventures, which, from what I remember, was pretty hard to come by back in the day. Basically it was the toolset that the Gold Box games were made from.
Besides the Eye of the Beholder and it's sequel, Eye of the Beholder II, there was also a little known title called Dungeon Hack. Based on the EoB engines, it was basically Nethack with a AD&D finish and a randomizable dungeon. It was darn hard. It even had a high score/deepest delver score, similar to Nethack's Graveyard. I only finished it once and yes, it was with a cleric and a ton of hammers and long hallways.
Hope some of this is useful. I miss those games. Wish I could buy them again, even with their weak 16 color EGA graphics.