High Court action has been taken by seven companies that together traded as Eurotunnel Plus, selling tickets to haulage companies across Europe on Eurotunnel’s behalf. The agency’s sales represented 45% of Eurotunnel’s lorry business.

The companies are seeking damages from five of their former employees, Ken Morrison, a Eurotunnel lawyer, Dirk Broek, Eurotunnel’s former commercial freight director, and Eurotunnel’s two main operating subsidiaries, The Channel Tunnel Group and France Manche.

Eurotunnel Plus alleges the defendants were involved in a “tortious conspiracy” aimed at damaging its business, which it values at more than €100m (£68m) a year.

It also claims damages for unlawful interference, breach of European competition rules, breach of contract and misuse of confidential information.

Eurotunnel, which is in the middle of crucial refinancing talks with its lenders, said last night it was aware of the legal action. “We will vigorously defend ourselves. It would be improper to make any further comment while the case is ongoing,” a spokesman said.

The case stems from a long-running battle over Eurotunnel’s plans to reshape its commercial strategy. Earlier this year the company’s new management — installed after a shareholder rebellion last year — unveiled Project Dare, the centrepiece of which was a plan to introduce a quota system for haulage companies. Eurotunnel dealt with its 150 biggest customers itself, with thousands of smaller companies buying tickets through Eurotunnel Plus.

Eurotunnel Plus rejected the quota plan, and eventually came to an arrangement that gave it an exemption. But earlier this year the tunnel company told the agency it planned to terminate its contract.

Eurotunnel Plus obtained an injunction in Paris blocking the move, but Eurotunnel announced earlier this month that it would terminate the deal from August 16, and would in future use the Eurotunnel Plus name itself.

In the High Court action, which is separate to the French proceedings, Eurotunnel Plus claims that in 2004 Eurotunnel began asking for detailed information on clients.

On April 1, three key employees sent resignation letters to Eurotunnel Plus. A few weeks later Eurotunnel sent letters to Eurotunnel Plus clients saying that Eurotunnel would be taking over the agency’s business.

The documents say e-mails retrieved from the employees’ laptops show they were “complicit” in writing the letters. Analysis of the laptops also showed “client information has been sent to and received by Eurotunnel”, as well as a list of Eurotunnel Plus staff and their salaries.

Eurotunnel Plus also alleges the tunnel company entered into an indemnity agreement with another of its key employees. The agreement was drawn up by outside solicitors.

This was to have protected her against “any liabilities ... as a result of any breach of her contract of employment ... and or breach of fiduciary duty”.

Eurotunnel is engaged in talks with its creditors about a renegotiation of its £6.6 billion debt mountain.

The company faces a financial crunch next year, when a mechanism that allows it to roll over interest payments comes to an end, guaranteed income levels from Eurostar trains cease, and it begins to be liable for the repayment for some of the debt’s principal.

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