A representative for Warner wrote in an e-mail message that “Warner Brothers has rights to the titles” in question and that “we vigorously protect all our copyrights. We do not make distinctions based on content.”

Image Despite efforts to suppress them, racist cartoons from the 1940s have been circulating on the Web. Above, Bugs Bunny outwits a rabbit hunter. Credit... Youtube

The cartoons, known as the “Censored 11,” have been unavailable to the public for 40 years. Postings no longer appear if YouTube is searched for “Coal Black and de Sebben Dwarfs,” a parody of “Snow White” and the most famous of the cartoons. But a search for “Coal Black” does find the cartoon.

These cartoons were controversial when first released; the N.A.A.C.P. unsuccessfully protested “Coal Black” before it was shown in 1943. Richard McIntire, the director of communications for the N.A.A.C.P., wrote in an e-mail message that “the cartoons are despicable. We encourage the films’ owners to maintain them as they are  that is, locked away in their vaults.”

WMAV01, a YouTube user who posted some of the cartoons and preferred not to give his name, wrote in an e-mail message that “these cartoons were never officially ‘banned’ by any law” and added that the cartoons had “historical value.” WMAV01 said the cartoons were available on Web sites like foundrymusic.com, which is run by “The Opie and Anthony Show,” a talk radio program.

The cartoons are also available on bootleg DVDs from Web sites like banned-cartoons.com, which sells a collection of 165 such cartoons. At least two of the shorts are available on unlicensed DVDs sold by third parties on Amazon.