The French like to do certain things en masse. Ever since 1789, it seems, French workers have preferred to operate in a crowd. Each summer, they take off for August altogether. And now, it turns out, they have applied the logic of the mass movement to insider dealing: more than 1,200 people, including 21 senior managers, are being investigated for shedding their stock in EADS, the European group that makes Airbus aircraft, before the bad news about the A380 and the A350 seeped out into the market.

The scale of suspect trades – ten million shares allegedly sold by more than a thousand company insiders for a collective profit of more than €90 million (£62 million) – suggests that insider dealing was not considered scandalous but standard practice. Call it the Franco-German business model: employees who know about technical problems in the company are allowed to sell their shares before the reality reaches the markets.

The facts are beyond parody. The French regulator, the AMF, has informed the Parisian prosecuting authorities that some of the most senior figures in the company sold shares before news of the problems with the aircraft were made public. Le Figaro reported that sellers of the stock included Arnaud Lagardère, then co-chairman of EADS; Thomas Enders and Noël Forgeard, the EADS joint chief executives at the time; some members of the company’s executive committee; and Airbus’s chief executive, Gustav Humbert. Apparently, all were well aware of the problems bedevilling the A380 and A350 at the time. The same, apparently, is true of strategic shareholders, Mr Lagardère and DaimlerChrysler. They are being looked at for forward-selling their stakes, apparently because they anticipated that the stock would fall. It did: when EADS issued a profits warning and reported its technical difficulties in June 2006, the share price fell by 26 per cent in a day.

Louis Gallois, the present EADS chief executive, played down the reports yesterday, saying that the investigation was at a preliminary stage – but he is wrong to make light of it. This not only threatens the integrity of EADS as a company, but it tarnishes the reputation of European business. It raises serious questions about the corporate culture on the Continent. It must, surely, prompt a wave of sackings across the top of the company. It is likely to result in a raft of lawsuits from past and present investors in EADS, not least BAE Systems, which saw more than a €1 billion wiped off the value of its former stake in the company.

But it is also a huge opportunity. Corrupt behaviour inside the company is a consequence of a rotten ownership structure outside it. Mr Gallois has the excuse to demand a radical restructuring.

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