Semtech ( SMTC) will restate financial reports dating back to 2002 as a result of discrepancies in its stock option-accounting practices, the company announced Thursday. The news comes a little over a month after the Camarillo, Calif., chipmaker began an internal review of its option practices in light of an informal inquiry by the Securities and Exchange Commission. The SEC and the U.S. Department of Justice are looking at several companies amid a widening controversy involving the so-called backdating of stock options. Semtech said that the special committee appointed by its board of directors has concluded that the accounting measurement dates for certain stock options granted between 1997 and 2002 differ from the measurement dates previously used for such awards. Consequently, the company expects to record additional noncash compensation expense and expects the amount to be material. The company also expects to restate its financial statements for fiscal years 2002 through 2006. The company also said it has been served with a third shareholder lawsuit related to its stock-option practices. Shares of Semtech slipped 3.9%, or 51 cents, to $12.68 in midday trading.