An agreement made between four-fifths of Deep Purple’s most successful lineup and their management companies has unfairly shut Ritchie Blackmore out of approximately a million dollars. That’s the claim the guitarist is making in a lawsuit.

The Daily Mail is reporting that Blackmore has filed suit against HEC Enterprises and Deep Purple (Overseas), after an audit of both discovered unreported royalties totaling a little more than £700,000 ($1.09 million), with the bulk of that sum coming from Deep Purple (Overseas). Adding in legal costs, Blackmore is suing for £750,000 ($1.16 million).

Back in 2003, the other members of Deep Purple’s 1969-73 lineup — Ian Gillan, Roger Glover, Jon Lord and Ian Paice — settled with the two companies without Blackmore’s involvement. He says he’s entitled to an equal share — one-fifth of up to 85 percent of the income from 14 albums. This includes their landmark 1972 record, Machine Head, which included “Smoke on the Water” and “Highway Star.”

Blackmore’s documents quote a former director of the companies as saying the he was owed more than £370,000 ($575,000), which has since been amended to £481,000 ($750,000).

Last week, Blackmore announced that he was returning to rock music. He has spent nearly 20 years with a folk project called Blackmore’s Night, who have a new album, All Our Yesterdays, coming out Sept. 18. Little detail about Blackmore’s next move is known, other than that he will start it in the summer fo 2016. It it is expected to be a tribute to his years in both Deep Purple and Rainbow, and that former Rainbow singer Joe Lynn Turner may be involved.

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