Société Générale is facing legal action from shareholders claiming the bank is involved in insider dealing as today it emerged that a non-executive director at the French bank sold off nearly €100 million worth of SocGen shares eight days before the discovery of "irregular trades" made by "rogue trader" Jérôme Kerviel.

Documents released by the AMF, the French market regulator, show that Robert A. Day, an non-executive director at Société Générale, sold off €85.7 million in shares on January 10. Also, two trusts connected to Mr Day, offloaded large chucks of shares on the same day - the Robert A. Day Foundation sold €8.6 million in stock and the Kelly Day Foundation sold €959,066.

In a document released at the "abnormal counterparty risk on a broker"weekend, Société Générale said that was detected "several days" before Mr Kerviel's superiors were informed on January 18.

Details of the share sales emerged as Mr Kerviel was charged with attempted fraud by the French financial police.

The man who lost his bank £3.7bn

Jerome Kerviel committed the biggest financial fraud in history after gambling away £3.7 billion on the stock market

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BACKGROUND

• Citigroup hammers SocGen on 'damaged credibility'

• French minister says €5bn trader 'acted alone'

• Furious Sarkozy kept in dark over €5bn fraud

• Chairman already faces laundering charges

Multimedia

• Video: Battered but not beaten

BACKGROUND

• Q&A: how the web of fictional clients was found

• What now for a proud bank laid low?

• Doubt over genius claims for €5bn fraudster

Related Links

• Societe Generale explains the fraud

• Timeline: How SocGen says it discovered the fraud

• Citigroup hammers SocGen on 'damaged credibility'

Paris prosecutor Jean-Claude Marin said that Mr Kerviel has admitted hacking into computers and faking e-mails to hide trades since 2005.

Mr Kerviel also disclosed that Eurex, the derivatives exchange controlled by the German stock exchange, contacted Société Générale in November 2007 to flag up Mr Kerviel's trades with France's second largest bank - two months before the irregular trades were fully investigated and announced to the market.

Mr Marin said: “Questioned by the bank, [Mr Kerviel] produced a fake document to justify the risk cover."

A group of around 100 Société Générale investors have brought a suit against the bank. Mr Day, 65, is the founder of TCW, a Los Angeles investment company which is a subsidiary of Société Générale's asset management group. TCW, based in Los Angeles, has a portfolio of $66 billion in collateralised debt obligations (CDOs) of which $52 billion are under management for Société Générale Asset Management.

CDOs are complex financial instruments which are often backed by sub-prime mortgage debt. Société Générale revealed last week it has €4.9 billion in CDOs backed by US sub-prime mortgage debt.

Today Citigroup cut the bank's possible target price by 50 per cent, saying the French bank is suffering "damaged credibility" and is unlikely to be taken over.

Citigroup, which downgraded the scandal-hit French bank’s shares from a "buy" to a "sell" also cut its target price from €130 per share to €65, reducing its market price tag from €72.9 billion to €36.4 billion.

The US investment bank said that it expects Société Générale’s earnings to fall by 31 per cent in 2008, after France's second largest bank discovered a €4.9 billion (£3.7 billion) alleged fraud it is blaming on Mr Kerviel.

Citigroup said: "SG still remains an attractive business ... however, we think an offer is unlikely to be forthcoming in the near term."

The bank is set to raise €5.5 billion through a rights issue to help plug its losses.

Société Générale will decide tomorrow whether to bring in an external firm to conduct a detailed audit of the bank's financials.

France's finance minister said today that Mr Kerviel acted alone when he made the "unauthorised trades".

Christine Lagarde's statement supports information released by Société Générale which said that it believed that Mr Kerviel was not complicit with any other individuals at the bank when he made the unauthorised trades.

At the weekend, Jean-Pierre Mustier, the head of Société Générale's finance and investment division said: "I cannot give you 100 per cent assurances that there were no accomplices, but at this stage, there is nothing pointing to the fact that he had accomplices, either internal or external."

In a formal statement last night, the trader's lawyers, Elisabeth Meyer and Christian Charrière-Bournazel, who is the head of the Paris Bar Association, said that their client had "committed no dishonest act, did not siphon off a single cent, and did not profit in any way".

Mr Kerviel's legal team said that the bank was trying to "create a smokescreen which would divert public attention from losses that were significantly more substantial than those it accumulated in recent months".

Société Générale has filed a criminal complaint, but police said that the case was so complex that they were still unclear of the nature of Mr Kerviel’s offences. Executives from the bank were called in to help police to understand how the trader masked thousands of transactions for about 13 months.

Eurex was unavailable for comment. A spokesman for Société Générale said the bank had already stated that Mr Kerviel had used false documents to cover his positions. The spokesman did not comment on whether Societe Generale had been contacted by Eurex in November. He declined to comment on the law suit filed against the bank.

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