The legal battle for control of the National Lottery, which appeared to have been concluded in November when Camelot cashed in its chips, has been revived by the company’s technology partner.

International Game Technology (IGT) is suing the Gambling Commission under European human rights laws, arguing the regulator’s decision to award the fourth lottery licence to the Czech-owned Allwyn gaming group had cost it “marketable goodwill”.

A legal victory for the Italian-owned IGT, which runs the lottery ticket machines at newsagents, supermarkets and garages, could lead to a damages award estimated at up to £600 million, payable from the National Lottery’s good causes fund.