Shares in Rambus dived more than 9 per cent in early trading in New York on Wednesday after the technology licensing company said an internal review found evidence of the backdating of executive stock options.
The company said it expected to restate financial statements to correct errors related to accounting for stock-based compensation expenses.
This followed a review by its audit committee of stock options practices and related accounting.
Rambus said its current quarterly report - to the end of June - would be delayed and that it may have to de-list its shares as a result.
It said the committee had reached a conclusion that the actual measurement dates for certain historical stock option grants differed from the recorded grant dates for such awards. But the company added the investigation was continuing and the committee examined the circumstances that gave rise to the differences.
The Rambus announcement comes amid a wdiening scandal over stock options practices. More than 60 companies, mainly in technology, are being investigated by the Securities and Exchange Commission or the Justice Department - in many cases both - over questionable timing of stockoptions grants.
Investigators want to know whether options were deliberately backdated to periods when a company’s stock price was at or near a record low and whether this was properly disclosed and accounted for.