NEW YORK (CNNMoney.com) -- While the number of companies implicated in the ongoing options back-dating imbroglio has cracked the 50-plus mark, a fair number of those companies may emerge from the saga unscathed, a new report suggests.

That's because it may be difficult, in many cases, to prove that companies actually back-dated options on purpose and failed to disclose it to investors, according to a report from the Corporate Library, a corporate governance research firm, which examined the 51 companies implicated through June 23.

"There needs to be instances of people changing documentation, for example, which is always very difficult to find out," said Paul Hodgson, senior research associate at the Corporate Library and author of the report. "You need to have a clear demonstration of intent rather than just bad judgment. It has to be intentional for it to be deemed fraudulent."

For example, companies that granted options relatively few times or adhered to an established policy for granting options may be less likely to face punishment, according to the report.

"The type of company that's going to be cleared is one that has a fairly regular option-granting process," said Hodgson. "It would indicate, one, that they have the right attitude, but also that they have the rules in place that will ensure that internal controls are being abided by."

On the other hand researchers who conducted the report also concluded that the presence of certain factors may lead to a higher probability that regulators will find that wrongdoing took place at a company.

Corporate Library researchers evaluated several factors in their review of the 51 companies, including corporate governance practices, options grant policies, stock incentive plan rules regarding setting exercise prices for options, authority to grant options and the timing of option grants.

Companies with poor historical corporate governance ratings, poor internal controls, a lax approach to discounted options and options granting authority, irregular stock option award dates, and equity plans that indemnified directors from fault may be more likely to be found guilty of back-dating and intentionally hiding it, according to the researchers.

But companies that only have a few or none of those problems may be absolved in the current investigations, the researchers found.

Michael Littenberg, a partner in New York-based law firm Schulte Roth and Zabel, said that in reviewing each case, the Securities and Exchange Commission and federal prosecutors will undoubtedly take such factors into consideration.

"They are likely to take into account the specific facts surrounding the grant - when it was granted, how much was granted, what was the dollar amount granted, was the employee senior, was it done by a prior management team, and did the company proactively disclose it," said Littenberg.

Regulators would likely take a different approach to a company that had one back-dated option grant for a thousand shares to one employee than it would to a company that back-dated a million shares to 50 people, Littenberg said.

It became harder to back-date options in 2002 with the passage of the Sarbanes-Oxley Act, which required companies to report options grants within two days of the date of the grant, according to Littenberg.

But Hodgson of the Corporate Library said it is not likely that the SEC is taking actions against companies who are reporting grants late, in part because the agency is likely understaffed to deal with such a tremendous amount of paperwork.

Hodgson also points out that if the number of companies gets higher, regulators will be hard-pressed to handle the workload.

"We've got 60-odd companies now," said Hodgson. "If there are many more then it's going to stretch the SEC's ability to handle these cases."

The number of companies that engaged in the practice could climb into the hundreds once more research is carried out, according to Erik Lie, an associate professor of finance at the University of Iowa. Lie's research attracted media and regulatory attention to the problem when he published a study noting that the granting of options to executives at several companies preceded big run-ups in the stock price.

Mukund Mohan, chief executive of Vangal, a consulting firm that advises companies facing crises related to their options granting practices, said companies are proactively reviewing their own practices.

"Every company that has been giving options to executives from 1995 to 2002 is doing an internal investigation - they are not being public about it, but every company is doing it," said Mohan, a former employee of Mercury Interactive (up $0.30 to $38.20, Charts), one of the first companies involved in the saga. Mercury replaced top executives and re-stated years of financial results over the scandal.

Mohan said that he expects most companies implicated to settle out of court, though he acknowledges that such a step will be tougher for smaller companies.

"Most small companies don't have $100 million lying around to deal with this," he said. "After settling (with regulators and the IRS) and legal fees, if you can settle for $30 million when it's all said and done, you're in a good place."

Attorneys say it is fairly likely that the SEC will look to enact new rules about options granting practices, but any new rules will likely focus on how companies disclose their practices to investors.

"What commissioners are contemplating is "more useful" disclosure with respect to back-dating," said Littenberg, who added that any new rules for options will likely focus on additional disclosure with respect to options that are already worth money when they are granted.

Related: More than 100 firms probably backdated options