According to a report in the Financial Times today, the lawsuit, which may go to court next month, is centred on Carlton believing it is owed a break-up fee for the failed plan.
The merger would have created an enlarged 拢7bn ITV group, but the merger failed when the Competition Commission stipulated that for the merger to go ahead United must sell its prized Meridian ITV franchise in the south of England.
The two argued that the condition "undermined the merger's rationale and significantly reduces benefits to shareholders" and so was called off.
United sold its ITV assets to Granada immediately, making the Manchester-based TV group the UK's biggest ITV company. The failed merger left the way open for Granada to seek an eventual merger with Carlton.
Yesterday, this moved a step closer as it emerged that the once-stalled merger plans between Carlton and Granada were back on.
The two companies rose on the news, with Carlton up by as much as 6.33% to 256.2p, while Granada was up 5.06% to 129.75p at one stage. Both dropped back in later trading.
The two are certain to get the go-ahead to merge when the government publishes its communications bill next week, in which it will lift rules standing in the way of a single ITV company. Under current legislation, broadcasters are prevented from owning more than 15% of the market.
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