In the cubicles and offices of Silicon Valley, some executives and company officials are quietly worrying about the impact of a jury's decision convicting former Brocade Communications Chief Executive Greg Reyes of securities fraud, according to several attorneys involved in other backdating cases.

Tuesday, Reyes was found guilty of 10 criminal charges, including conspiracy and securities fraud, in the first criminal case associated with stock-option backdating. Many local attorneys following the case had predicted the prosecution would have a tough time proving that Reyes intended to defraud investors in part because he did not personally benefit.

"Before, people were waiting and holding their breath," said Darren Robbins, an attorney at Lerach Coughlin Stoia Geller Rudman & Robbins in San Diego who is involved in several cases against companies still under investigation by regulators and the Department of Justice. "Many defendants are, at least what we are hearing, is they are trying to pick themselves back up from the surprise."

Since the first disclosures of stock-option backdating in early 2005, more than 200 investigations have been launched nationwide. In the valley, where the biggest number of internal and outside probes are being conducted, there have been two indictments. In addition to Reyes, who plans to appeal, prosecutors earlier this year filed a criminal case against Kent Roberts, the former general counsel at McAfee.

Backdating refers to the practice of going back in time, typically to when a stock's price was lower, to pick the date for option grants, increasing the odds that the recipient could sell the stock at a profit. While the practice is not illegal, prosecutors said failing to disclose the change and the impact on a company's financial statements is fraudulent.

Some executives who already have participated in a company's internal investigation may be especially nervous, said Christopher Cooke, a partner with Cooke, Kobrick & Wu in San Mateo and a former enforcement attorney with the Securities and Exchange Commission.

That's because one of the key pieces of testimony in the Reyes case came from Craig Martin, an attorney who conducted Brocade's internal investigation. Martin testified that Reyes told him the company did not engage in backdating, contradicting a key part of the defense argument.

During the trial, Reyes' attorneys acknowledged that Brocade had engaged in periodic backdating to hire the best talent. But they said the company's finance department believed it had properly accounted for the option grants, that Reyes relied on their expertise and that he had no intent to deceive or defraud investors and regulators.

"It would make CEOs who were asked to provide information to their audit committee pretty nervous about doing that," Cooke said. "If the clients say anything that can be shown to be inconsistent," he said, that could later come back to haunt them as evidence of intent.

Matt Jacobs, an attorney with McDermott Will & Emery in Palo Alto and a former assistant U.S. attorney for the Northern District, said, "Certainly, everyone involved in these cases has taken note of the jury's verdict, and the government will probably be emboldened to bring more criminal cases."

He noted that there are still many cases in which the Justice Department hasn't made a decision about whether to pursue criminal charges.

But many other attorneys say every case is different and that Reyes' conviction may not spawn more criminal charges. Prosecutors in Reyes' case, in an interview with the Mercury News on Wednesday, gave no indication that they plan to unleash new criminal charges anytime soon.

"It does depend on the facts of a particular case," said Assistant U.S. Attorney Tim Crudo. "I don't know if it's helpful to lump them all together."