PARIS - In a bizarre ending to a 14-year-old investigation, a French court convicted American financier George Soros yesterday of insider trading and fined him 2.2 million euros, or about $2.3 million.

The verdict by the three-member bench came after a prosecutor recommended during a hearing last month that, at the minimum, Soros should be fined 2.2 million euros, the sum he is accused of having earned on what officials say were illegal transactions.

In a statement, Soros, who was in New York yesterday, expressed his belief that the charges against him were "unfounded and without merit" and said he was "astonished and dismayed by the court's ruling."

Declaring that he would appeal the decision "to the highest level necessary," Soros said, "At no point was I in possession of inside information regarding Societe Generale."

Michael Vachon, a spokesman for Soros, said by telephone from New York that Soros "is sort of taking it in. It is a shock."

Two other defendants, Jean-Charles Naouri, 53, a former senior official in the French Finance Ministry, and Samir Traboulsi, 64, a French citizen of Lebanese origin, were acquitted. The prosecutor had recommended fines for both men.

Soros is best known for his wildly successful investing, but also for his philanthropy, most notably in formerly Communist Eastern Europe. In the 1980s, he acquired stakes valued about $50 million in four formerly state-owned companies in France, including the bank Societe Generale. The stakes were purchased in 1988 for Soros' Quantum Fund.

The case drew interest here partly because of Soros' image as the paradigm of the free-wheeling financier and partly because it illustrated some of the anomalies of financial oversight in France.

The case dates to the privatization by a center-right government in 1987 of Societe Generale, a major French banking company that until then was government-owned. The next year, a Socialist-led government returned to office and sought to regain control of the bank. Sensing an opportunity for gain, while assisting their political allies, a group of investors around the French financier Georges Pebereau devised a scheme to acquire control of the bank, sending its share price soaring.

Pebereau's raid was ultimately unsuccessful, but in September 1988 an associate of Pebereau informed Soros in a telephone conversation of the planned bid, according to trial testimony.

Soros' lawyers argued that the information Soros received was not sufficiently confidential to substantiate the charge of insider trading. Moreover, they argued that until new legislation relating to insider trading was enacted in 1990, the offense was limited to employees purchasing shares in their own companies.

Possible appeals

Lawyers for Soros said the case could be appealed in France and to the European Court of Justice in Luxembourg. One of their strongest arguments would be the length of the proceedings. In the past, cases that have dragged on for as few as five years have been overturned by European courts on appeal.

In an appearance before the court last month, Soros said: ''I have been in business all my life, and I think I know what is insider trading, and what isn't."

Yesterday's ruling marked the first time that Soros has been convicted of financial misdeeds. In 1979, he signed a consent decree with the Securities and Exchange Commission in a civil proceeding relating to his purchase of shares in an American computer manufacturer that was about to issue fresh shares of stock.

SEC officials contended that Soros had sold shares to push down the price of the new shares. Soros acknowledged no wrongdoing, but agreed not to engage in similar practices in the future.

While the current case drew attention because of Soros' fame in financial circles, it was also seen as illustrative of the ill-functioning of financial control and the court system in France. Prosecutors replied to criticism of the extraordinary lapse of time between the events and the trial by pointing to delays in obtaining financial documentation relating to the trial from other European countries, notably Switzerland.

In fact, Pebereau's unsuccessful bid for Societe Generale formed part of a political intrigue involving efforts by former President Francois Mitterrand, who sought after his re-election in 1988 to bring several large French companies into the sphere of investors inclined to Mitterrand's Socialist party.

Early in investigation

An early investigation into the events by the French stock market oversight agency made little mention of Soros. Not until after 1992 did the prosecutors question him about his role in the affair. None of the key participants in Pebereau's scheme, including the former chairman of the L'Oreal cosmetics group, Francois Dalle, and the French founder of the Perrier water group, Gustave Leven, were brought to trial.

Soros' lawyer, Bernard du Granrut, told reporters yesterday that "an entire range of quite particular issues that we raised were not even considered by the court."