Valve is continuing to sue Vivendi about a case that got started in 2002 regarding Sierra games. Sierra, of course, was owned by Vivendi...
only now that Activision has merged with Vivendi Games to form Activision Blizzard (keep up!), Valve is having to sue Activision Blizzard as 'successor-in-interest'.
Basically, Sierra had agreed to distribute Valve games.
According
Gamepolitics (
which has a link to the court documents), the case revolves around licensing rights to games used in cyber-cafes.
The case, of course, is all about the money: on April 6th, a legal arbitration awarded Valve $2,391,932 for unpaid royalties. Valve sulked a little at the size of the award, but agreed to abide by the decision. Activision/Blizzard didn't just sulk, it refused to pay, stating that Valve had been overpaid by $424,136 in the past.
Instead, Activision/Blizzard sent Valve the sum of $1,967,796 (that's the first figure minus the second figure). It also pointed out that if Valve sued, it would counter-sue.
Valve has sued.