Credit: Osbourne: Jason Sheldon/Landov; Iommi: Brian Hineline/Retna Ltd

We’re used to Ozzy Osbourne riding the “Crazy Train.” But apparently, the ex-Black Sabbath frontman has boarded a less-obviously-nuts mode of transport — and it’s headed towards a court of law.

According to the New York Post, Osbourne is suing Sabs guitarist Tony Iommi for a 50% interest in the BS name and a portion of Iommi’s profits. The suit also asserts Iommi illegally claimed ownership of the Sabbath moniker, and that Black Sabbath’s popularity decreased following Osbourne’s departure — which, apart from anything else, adds another chapter to Ozzy’s feud with his Sabs successor Ronnie James Dio.

It’s always regrettable when former bandmates fall out like this. Unless you’re a lawyer, of course. Those guys love this stuff! But what do you think? Does this signal the final end of Osbourne and Iommi’s partnership? Has Ozzy gone off the rails? And how are you liking these train jokes?

Update, 5.30 PM EST, May 29, 2009: Ozzy Osbourne has issued the following statement…

“It is with great regret that I had to resort to legal action against my long term partner, Tony Iommi, but after three years of trying to resolve this issue amicably, I feel I have no other recourse. As of the mid-1990’s, after constant and numerous changes in band members, the brand of “Black Sabbath” was literally in the toilet and Tony Iommi (touring under the name Black Sabbath) was reduced to performing in clubs. Since 1997 when Geezer, Bill and myself rejoined the band, Black Sabbath has returned to its former glory as we headlined sold-out arenas and amphitheatres playing to upwards of 50,000 people at each show around the world. We worked collectively to restore credibility and bring dignity back to the name “Black Sabbath” which lead to the band being inducted into the UK and US Rock & Roll Hall of Fames in 2005 and 2006, respectively. Throughout the last 12 years, it was my management representatives who oversaw the marketing and quality control of the “Black Sabbath” brand through OZZFEST, touring, merchandising and album reissues. The name “Black Sabbath” now has a worldwide prestige and merchandising value that it would not have had by continuing on the road it was on prior to the 1997 reunion tour. Tony, I am so sorry it’s had to get to this point by me having to take this action against you. I don’t have the right to speak for Geezer and Bill, but I feel that morally and ethically the trademark should be owned by the four of us equally. I hope that by me taking this first step that it will ultimately end up that way. We’ve all worked too hard and long in our careers to allow you to sell merchandise that features all our faces, old Black Sabbath album covers and band logos, and then you tell us that you own the copyright. We’re all in our 60’s now. The Black Sabbath legacy should live on long after we have all gone. Please do the right thing.”