The U.S. Securities and Exchange Commission has charged two current and two former officers of semiconductor vendor Broadcom for their alleged participation in a supposed five-year scheme to backdate stock options granted to almost all of the company's employees.

The SEC's complaint, filed Wednesday in U.S. District Court for the Central District of California, alleges that Broadcom's current Chairman and Chief Technology Officer Henry Samueli, current General Counsel David Dull, former CEO Henry Nicholas, and former Chief Financial Officer William Ruehle participated in a scheme lasting from 1998 to 2003 to fraudulently backdate stock option grants, resulting in the company failing to record billions of dollars in compensation expenses.

The complaint also accuses the four men of falsifying documents to cover up the backdating, the SEC said.

Two Broadcom spokespeople weren't immediately available for comment Wednesday.

Broadcom restated its financial results in January 2007 and reported more than $2 billion in additional compensation expenses. The SEC has brought backdating charges against several tech vendors in recent years.

The Broadcom executives "perpetrated a massive, five-year scheme that involved fraudulent backdating of dozens of option grants, falsifying corporate records, intentionally false accounting, and lying to shareholders," Linda Chatman Thomsen, director of the SEC's Division of Enforcement, said in a statement. "This egregious misconduct resulted in the largest accounting restatement to date arising from stock option backdating and warrants the significant sanctions sought from these individuals."

The four executives made it appear that the options were granted at times when Broadcom's stock was selling for low prices, although the options weren't granted at those times, the SEC said.

Nicholas and Samueli served on the two-member option committee that had authority to approve options to employees and all but the most senior officers, the SEC said. The option committee approved up to 88 grants during the time period in question, but in many cases, the committee didn't hold meetings or make decisions on the dates the grants were supposedly approved, the SEC said.

Instead, Ruehle allegedly selected most of the grant dates retroactively based on a comparison of Broadcom's historical stock prices, and Nicholas and Samueli allegedly concealed the backdating by signing false committee written consents stating that the grant had been approved by the retroactive date, the SEC alleged.

In addition, Nicholas, Samueli, and Ruehle decided on option grants to Broadcom's senior officers and used hindsight to select the dates for them, instead of having an independent compensation committee approve those grants, the SEC alleged.

Dull allegedly knew about the backdating scheme and was involved in the preparation and approval of false board and compensation committee meeting documents to conceal two backdated grants in 2001, the SEC said. In one case, the officers awarded him options to purchase 300,000 shares, the agency said.

Ruehle received options worth more than $100,000 and Dull received options worth more than $1.8 million in the backdating scheme, the SEC alleged.

The SEC charged Nicholas, Samueli, Ruehle, and Dull with violating or aiding and abetting violations of the antifraud, record-keeping, financial reporting, and internal controls provisions of the federal securities laws.

The SEC also alleged that Nicholas and Ruehle violated the proxy and false statements to auditors provisions and signed certifications required by the Sarbanes-Oxley Act of 2002 that were false and misleading concerning Broadcom's 2002 through 2005 periodic reports. In addition, the SEC alleged that Ruehle and Dull violated the securities ownership reporting provisions.

The agency is seeking several penalties, including civil fines, the barring of the men from serving as officers or directors, and the reimbursement of bonuses and profits from stock sales by Nicholas and Ruehle, the SEC said.

Previously, the SEC has brought enforcement actions against Broadcom and Broadcom's former vice president of human resources, Nancy Tullos, in connection with the alleged backdating scheme.