KLA-Tencor's

(KLAC) - Get Report

top lawyer stepped down Monday as the company said it has wrapped up an internal investigation into past stock option accounting practices.

The San Jose, Calif., chip-equipment maker also pointed a finger at its former chief executive, saying it has "terminated all aspects of its employment relationship with Kenneth L. Schroeder, effective immediately."

KLA said it now expects to record up to $400 million in noncash charges as a result of incorrect measurement dates for certain stock option grants between 1997 and 2002.

The executive departures come a week after senior management at

CNet

(CNET) - Get Report

and

McAfee

(MFE)

headed for the exits under similar circumstances.

KLA is among more than 100 companies under scrutiny for the practice of backdating stock options. In June, KLA said it had detected discrepancies between the measurement dates and the recorded grant dates of certain past stock option grants.

Like many companies caught up in the backdating mess, KLA has received subpoenas from the Justice Department regarding the matter.

KLA said Monday that it expects to name an interim general counsel soon to replace Stuart Nichols, who served as the company's general counsel since 2000 and has resigned effective immediately.

KLA said it has repriced all outstanding retroactively priced stock options held by Nichols and canclled all such options held by former CEO Schroeder. He served as CEO between 1999 and 2005.

The company said it has concluded that there was no involvement in the improper stock-options practices by any current members of management, including CEO Richard Wallace, COO John Kispert and CFO Jeffrey Hall, all of whom assumed their current roles in early 2006.

Because Kispert served as CFO during part of the period of improper stock option practices, his outstanding retroactively priced stock options will be repriced.

KLA said it is still working to determine the exact amount of noncash charges for stock-based compensation expenses and the specific periods that will require financial restatements.

Shares of KLA rose 41 cents after hours to $49.95.