SAN FRANCISCO (Bloomberg) — Bermuda-based Marvell Technology Group Ltd. may restate results by as much as $350 million to account for stock-options costs, and removed several executives after a review found they backdated grants.Chief executive officer Sehat Sutardja, who participated in "a few instances," will step down as chairman, Marvell said yesterday in a statement. The company fired Matthew Gloss, former general counsel for the US, and said chief financial officer George Hervey resigned.

Marvell, which makes chips used in consumer products such as Apple Inc.'s iPod music and video player, is among more than 200 companies that have disclosed internal or federal probes into whether executives backdated options. Half of those have restated results, leading to costs exceeding $11.3 billion.

The company demoted chief operating officer Weili Dai, also a co-founder, to director of business development, a role that carries no responsibility for financial matters.

Marvell, which is run from Santa Clara, California, will seek replacements for all three executives and hire three independent directors, one of whom will succeed Sutardja as chairman.

Marvell shares rose 22 cents, or 1.3 percent, to $17.82 at 12:07 p.m. New York time in Nasdaq Stock Market trading. Before yesterday, they had dropped 8.3 percent this year.

On April 24, Marvell said the US Securities and Exchange Commission had escalated its interest in the company's options practices to a formal investigation. Marvell first received a letter of informal inquiry in July last year requesting certain documents.