This one seems to have slipped under the radar. In the EU, you cannot geo-block products bought in one EU country, when they are used in another. There is a single EU digital market, if you buy within the EU, you can use the product in the EU.
In this case, the companies were selling the games in the former Eastern Block countries at huge discounts, as the average wages there are lower. Games across Europe took advantage of the cheap prices, but when they tried to activate them through Steam, they were told that the games were restricted to those former Eastern Block countries - illegal under EU law.
Total fines were just short of $10 million. All the companies, apart from Valve, co-operated with the investigation, which is why Valve got hit the hardest. Valve’s attitude of “they told us to do it, so we aren’t involved!” Didn’t go down well with the authorities in the EU.