Two Russian businessmen are fighting over a stake in fishing company Norebo Holding, which made Vitaly Orlov a billionaire. Alexander Tugushev is suing Orlov, a one-time friend and associate, in London for a third of the company, reports Bloomberg.

Orlov took control of Norebo in 2016 after building a fortune from 25 years working in the fishing industry. The business is now benefiting from sanctions that limit food imports to Russia, Bloomberg said.

Tugushev’s lawyers said in court documents for a hearing this week he “has been the victim of a complex and sophisticated conspiracy” by Orlov and another co-founder of the business to deny his investment in the company.