Videos will not be pulled from iTunes for several months, as the current two-year contract between Apple and NBC runs through December. If and when they disappear however, it may have a dramatic impact on iTunes, as NBC is the top supplier to the store, supplying approximately 40 percent of all video, or 1,500 hours. Some of the most popular series belong to the network: these include "Battlestar Galactica" and "The Office." The Times' source suggests that the content may yet remain, but this depends on a new contract being agreed to in the short time before the prior one expires. Both companies are still said to be involved in talks, the NBC announcement being a necessary 90-day warning to prevent its deal from renewing. Similar warning deadlines may be coming up for the likes of CBS, Discovery and the News Corporation. Many companies are said to be upset with Apple, accusing the company of underpricing iTunes content in order to sell iPods and accessories. Most recently, the Universal Music Group decided to switch from a contract to an "at will" relationship with Apple, and has deliberately excluded Apple from its tests of DRM-free music.