Driven by ad revenues, acquisition of MediaDefender.

ArtistDirect reports fourth quarter revenues increased 246% to $5.6 million driven by an expansion of ad revenues and the acquisition of anti-piracy specialist MediaDefender. The company’s net loss grew to $302,000, or 7 cents per share from $29,000, or 1 cent per share a year ago.

Anti-piracy services now ranks as ArtistDirect’s top source of revenue. MediaDefender, acquired in July of last year, posted $3.6 million in fourth quarter revenue while advertising revenues grew 44% to $1.2 million. E-Commerce revenues declined 3% to $775,000.

For the full year ended December 31, 2005, revenue increased 172% to $13.9 million. ArtistDirect trimmed its net loss to $744,000, or 1 cent per share, from $1.1 million, or 30 cents per share, in 2004. Adjusted EBITDA for the year totaled $3,237,000, vs. a loss of $862,000 in 2004.

Shares in ArtistDirect were off over 6% in late day trading at $4.15. The company’s stock is up close to 50% since its acquisition of MediaDefender.