Vitesse Semiconductor (VTSS) put three top executives including its CEO on leave as the board appointed a special panel to investigate possible backdating of stock option grants.

The Camarillo, Calif., chip company said the board panel will "conduct an internal investigation relating to past stock option grants, the timing of such grants and related accounting and documentation. The Special Committee is being assisted by independent outside legal counsel."

Vitesse says CEO Louis R. Tomasetta, exec VP Eugene F. Hovanec and finance chief Yatin Mody have been placed on administrative leave. Chris Gardner has been named acting CEO.

Questions about options pricing and possible backdating have plagued giant health insurer

UnitedHealth

(UNH) - Get Report

ever since a report last week by

The Wall Street Journal

. The Minnesota company says its board is looking into the matter.

Vitesse said the probe could lead to a restatement. Its shares rose 6 cents to $3.17.