Gemstar-TV Guide International will be bought by Macrovision in a deal worth $2.8 billion, Reuters says. The deal is unusual for several reasons; among these is the fact that Gemstar is actually larger than Macrovision, requiring the latter company to enter $800 million in new debt, which in turn has triggered a 25 percent drop in its stock. For most people, however, the deal is important because Macrovision is responsible for the CSS copy protection on DVDs, and Gemstar produces both TV Guide magazine and similarly-themed TV channels.