Lawyers for Scottish & Newcastle , the brewer under siege from Carlsberg and Heineken, have written to its continental suitors and their advisers, warning them against using confidential information on Baltic Beverages Holding in formulating their bid, The Times has learnt.

The value of BBH, a 50-50 joint venture between Carlsberg and S&N, is seen as critical to the outcome of the bid for Britain’s biggest brewer. However, confidentiality clauses governing the joint venture mean that S&N shareholders have not been given access to future profit projections.

S&N has sought to persuade Carlsberg to agree to release full projections to allow its shareholders to assess the merits of the bidding consortium’s indicative 750p-a-share offer. Two leading shareholders, Legal & General and Scottish Widows, have publicly called on the Danish brewer to release the information.

But Carlsberg has steadfastly refused to do so, and last month lawyers for the Danish company sent letters to S&N’s directors warning them to withhold all information regarding BBH. The letter warned that Carlsberg would “take all necessary legal measures to protect its interests”.

In a move that is likely to be seen as a tit-for-tat riposte, S&N’s lawyers, Linklaters and the Swedish firm Ham-marskiöld, are understood to have written to the joint bidders and their advisers warning them against the use of confidential BBH information.

John Dunsmore, the S&N chief executive, recently suggested that, by being party to a joint bid, Heineken was guilty of “indirectly misuing” confidential information on BBH, even if it had not been given information directly by its partner.

The accusation also forms part of the Swedish arbitration case launched by S&N under the terms of the BBH shareholders agreement. S&N claims that by launching a joint bid with Heineken, Carlsberg has breached that agreement by seeking to circumvent a so-called shotgun clause governing how one party can seek to buy out the other.

The Edinburgh company claims that Carlsberg’s actions mean it should be forced to sell to S&N its 50 per cent of BBH, which operates in Russia and the Baltics but is registered in Sweden. The Stockholm Chamber of Commerce confirmed yesterday that it had appointed a chairman to the arbitration tribunal. The process is expected to take 6 to 12 months.

Some observers believe Carlsberg’s unwillingness to reveal full projections for BBH risks creating a false market. “It is a very unusual, possibly unique situation,” one analyst said. “What you’ve got is a joint bid in which one of the bidders has access to crucial information that is not available to the shareholders of the target company.”

“ Another analyst suggested that the issue of a false market should be looked at by the Takeover Panel, even though the bidding consortium has so far refrained from buying S&N shares in the market. “I believe the Takeover Panel should look at this issue as a matter of urgency. There is an argument for describing what’s happening as a case of insider trading.”

Carlsberg and Heineken first approached S&N in October with an indicative offer worth 720p-a-share. The following month this was raised to 750p, valuing its target at £7.3 billion, or about £9.7 billion including debt and pension liabilities. S&N has steadfastly refused to discuss the bid with the consortium, insisting the level of the bid undervalues not only its BBH stake but also the rest of its businesses.

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