As of midday on Wednesday, shares in the company, which primarily rents textbooks via its website, were down 20 percent below their initial public offering price.
The activist investor has made enormous profits from his year-old bet on Netflix, having disclosed on Tuesday that he has halved his stake to about 4.5 percent.
Pierre Omidyar will finance the news site drawing Glenn Greenwald away from The Guardian, where he reported on the revelations by Edward Snowden.
Walt Mossberg and Kara Swisher, co-editors of the All Things Digital news site, will depart at the end of the year.
Chegg, a start-up focused on the business of renting textbooks, filed for an initial public offering on Wednesday, intending to use the proceeds to raise additional capital and reduce debt.
Deals to buy The Washington Post and The Boston Globe have been announced this week by very wealthy entrepreneurs.
The company plans to hold onto all of its vast entertainment arm, rejecting a proposal by one of its biggest investors, the activist hedge fund manager Daniel S. Loeb.
Barnes & Noble reported a bigger loss for the fiscal fourth quarter than analysts expected, and conceded that its Nook cannot compete with other color e-readers.
Major media companies, including Condé Nast, Yahoo and Hulu, are promoting online video programming on a large scale, but it is not clear whether advertising dollars will follow.
Bloomberg L.P. announced that it was incorporating tweets into its data service, allowing traders and other professionals to monitor social media buzz and important news about companies they follow.
Andrés Rodríguez, the publisher and founder of SpainMedia, has much at stake in the debut this month of a Spanish-language edition of Forbes, the American business magazine.
Guggenheim Partners said on Tuesday that it had hired Ross Levinsohn, a former Yahoo chief executive, to lead a new media unit that includes Billboard, Adweek and the Hollywood Reporter.