District Judge Dean Pregerson granted an injunction blocking Howard Mann from using his sites including MJgives.com and michaeljacksonsecretvault.com.

The sites featured Jackson video clips, art from This Is It and Jackson logos.

Jackson's estate sued Mann over copyright and unfair competition.

The estate holds the copyright to Jackson's image and music for the benefit of the singer's mother Katherine and his three children.

Judge Pregerson said: "There is undisputed evidence that (Mann) intended in bad faith to profit from use of Jackson's name, by registering multiple domain names containing his name or the initials MJ to sell Jackson-related products."

Mann was not unknown to the Jackson family. He had worked with Michael Jackson's mother Katherine on several projects since 2009.

These projects included a book published in 2010 entitled Never Can Say Goodbye, which featured recollections of her son, as well as a DVD and calendar containing exclusive photos and video.

All were sold through Mann's "secretvault" website.

Mann said he obtained the rights to the material at a bankruptcy sale involving members of Jackson's family several years ago.

Jackson estate executors John McClain and John Branca said in a statement they were "extremely pleased" with the court's ruling which will prevent Mann from "continuing to unlawfully profit from Michael Jackson and his intellectual property".

A further court hearing on 4 September will decide how much Mann will have to pay in damages to the Jackson estate.