A special committee within Activision (NASDAQ: ATVI) found it had improperly dated over 3000 stock options, resulting in a pre-tax charge of $66.7 million, according to a securities filing.

The Securities and Exchange Commission launched a formal probe into the backdating at the company, Activision said Thursday in an amendment to its quarterly report file with the Securities and Exchange Commission.

The majority of the grants requiring measurement date corrections occurred on 16 dates over a 15-year period, the company said.

Backdating is when options are issued to coincide with low points in the stock price. It can increase the profit for the recipient, but is not illegal itself. However it must be properly reported to investors.

The committee said it found no intentional wrongdoing at the company. It said neither the company or the company's top executives engaged in intentional wrongdoing.

The report mentioned CEO Robert Kotick, Co-Chairman Brian Kelly, Senior Advisor Ronald Doomink and General Counsel George Rose.

Shares of Activision rose 15 cents, or 0.81 percent to reach $18.61 in mi-day trading on the Nasdaq Stock Market.