Memory chip technology vendor Rambus expects to take a $200 million charge to earnings for stock-option backdating.

On Thursday, the company released the conclusions of an internal audit of its finances. along with an abbreviated financial report for the third quarter of 2006.

Rambus, which licenses high-speed chip interface designs to other technology companies, said it examined 200 stock option grants going back to 1998 and found that a significant number of the stock option grants were not correctly accounted for.

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Rambus is one of more than 100 companies implicated this year in a scandal involving backdating of stock options. In backdating, companies move the date of a stock-option grant to a time when the company’s stock was worth less. That can give employees bigger profits — at the expense of other shareholders — when they exercise their options.

Rambus said its investigation showed that most of the backdating occurred on options granted between 1998 and 2001. The company said its audit showed that in many cases the appropriate measurement dates for option grants differed from the recorded grant dates.

From 1999 through 2003, the report said, Rambus regularly issued grants to new hires by selecting the lowest price of the quarter between the employee’s start date and the end of the quarter. But on certain occasions, the employee’s formal start date was moved back from the day they started working so they would qualify for a lower option price.

The audit identified other instances of backdating in 2003 and 2004.

Former Rambus chief executive officer Geoff Tate resigned from the company’s board on Aug. 16. Tate served as CEO between 1990 and 2005, including the period when the problems allegedly occurred. During that time, Tate was the sole member of the committee that granted options at Rambus.

Rambus was unable to post financial results for the second and third quarters of 2006 while it conducted the investigation, which puts the company in danger of being delisted from the Nasdaq. It is negotiating with Nasdaq officials for an extension until Dec. 19 to come into compliance with listing qualifications.

On Thursday, the company reported revenue for the third quarter but not earnings. For the quarter, ended Sept. 30, Rambus reported income of $45.9 million. That was up 28 percent from the third quarter of 2006, but down 6 percent from the previous quarter.