The European Court of Human Rights has ruled that France did not violate financier George Soros' rights when convicting him of insider trading.

Soros was fined 940,000 euros ($1.3 million) in 2007 for purchasing Societe Generale shares in 1988, days after being informed about a planned takeover bid for the bank.

Soros argued that France's insider trading rules at the time were unclear, and that the length of the investigation made it difficult to call reliable witnesses and violated his right to a fair trial.

The European court, based in Strasbourg, France, ruled Thursday there were no violations. It said "the law applicable in 1988 was sufficient for Soros to have been aware that his conduct might be unlawful."

The Hungarian-born businessman and philanthropist has sought for years to clear his name.