Colin Veitch, a former chief executive at Norwegian Cruise Lines, filed the suit in U.S. District Court in Miami, asking for unspecified damages and demanding that Branson's company cease from moving ahead with the launch of Virgin Cruises.
In December, Virgin revealed plans to launch Virgin Cruises, naming Tom McAlpin, a former president at Disney Cruise Line, to be chief executive. No launch date was announced.
The 209-page suit includes documents that, according to Veitch, show that he reached an agreement with Virgin in 2011 to work together on the launch of the cruise line. The suit claims Virgin backed out of the agreement with Veitch but pursued the idea anyway.
"Virgin's proceeding with the Virgin Cruises business is in breach of the non-disclosure and not-use agreement it signed with Mr. Veitch," the lawsuit claims.
The lawsuit does not call for a specific amount in damages but says that Veitch would have been paid $315 million if the cruise line had been successful.
Virgin Group has rejected Veitch's claim, saying Branson and his company have been looking into the cruise market since the late 1970s.
"Over the years, we have been in discussions with a number of parties including the plaintiff, and those discussions ceased in 2012," Virgin Group said in a statement. "We strongly believe the claim has no merits."
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