Blizzard Entertainment Inc.’s release of Diablo III has broken the record for the fastest-selling PC game in its first 24 hours on the market.

The Irvine-based online-video game maker said Wednesday the game sold 3.5 million copies on May 15, the day it went on sale.

That’s not including 1.2 million players who received Diablo III as part of their yearly subscriptions for World of Warcraft.

The previous record was held by another Blizzard title, World of Warcraft: Cataclysm, the game’s third expansion set.

Cataclysm sold 3.3 million copies in the first 24 hours it went on sale in December 2010.

Investors sent shares of Blizzard’s Santa Monica-based parent Activision Blizzard Inc. up nearly 2% in afternoon New York trading to market value of about $13.55 billion.

Blizzard, which is ultimately part of Vivendi SA in France, is the largest software maker in Orange County and employs about 1,000 people here.