Investing: E*Trade Financial said yesterday that it would fully reimburse any customer who is the victim of fraudulent activity - the first online brokerage company to offer the kind of protection that users of credit and debit cards receive.

While the announcement may be more of a sales pitch than a security protection given the token amounts of money lost to fraud, it may encourage E*Trade's competitors like Ameritrade and Charles Schwab to follow suit. The new policy is a major shift for the online brokerage industry, which typically puts the onus of security on the investor.

Banks that issue credit cards have been required to bear the brunt of fraud losses since Congress passed a law limiting consumer liability to $50 in the 1970's. Debit cards face somewhat more relaxed requirements; the consumer can be responsible for $50 to as much as the entire amount stolen as well as any funds in linked accounts, depending on when the incident is reported. Today, however, most credit and debit cards come with "zero-liability protection," with the banks agreeing to cover the cost of fraud.

"You have to make the entity in the position to solve the problem, responsible for the problem," said Bruce Schneier, the chief technology officer of Counterpane Internet Security. "Otherwise, it doesn't get solved."

The online brokerage industry, on the other hand, has never had any fraud loss obligations.

"Only in brokerage is there this gray area where the customer stands out there on your own; we don't think this is going to last," said R. Jarrett Lillien, the chief executive of E*Trade. "If the customer thinks we should be responsible, we should be responsible."

"We think the industry is going to step up," he added.

The Securities and Exchange Commission has warned against the threat of data theft and encourages investors to bolster the security of their financial accounts. It suggests using firewalls or installing anti-spyware, anti-virus, and anti-spam features. The S.E.C. also encourages additional layers of protection, like hardware security tokens with encrypted personal information. However, it has not issued specific guidelines like the ones provided last year by the Federal Financial Institutions Examination Council, a group of the five national banking regulators.

"Large firms must guard against identity-theft schemes at any point of contacts with customers," said John Nester, an S.E.C. spokesman.

"There is no prescriptive rule but they have to take steps to participate and address the security threats," he added. "However, the staff is currently considering whether there needs to be S.E.C, rule-making to provide firms with additional direction."

E*Trade's announcement may allow it to be ahead of any future regulation, and it addresses a growing threat of data theft.

Just a few years ago, a data breach was all but unheard-of in the online brokerage business. Today, the S.E.C. says it is aware of dozens of cases.

In many of them, data thieves have been able to gain access to an investor's system by installing software that tracks the keystrokes when an investor logs into a brokerage account. The thief, in turn, uses that information to log into the account and withdraw the money or wire it elsewhere.

"We don't know the number of people who have been harmed, but we do know that the people who have been harmed have been to the tune of hundreds of thousands of dollars," said Gerri Walsh, acting director of the S.E.C.'s Office of Investor Education.

At E*Trade, Mr. Lillien said that the number of online fraud cases was growing but totaled fewer than 50 last year. The cost of fraud at E*Trade, he added, has also grown from a few thousand dollars a year several years ago to about $2 million a year, or about 0.2 percent of its revenues.

"It is not a big issue today, but the industry should get together and take responsibility and nip this in the bud," he said. Competitors say that fraud levels are increasing but remain low, and they provide customers with software tools and educational materials for safeguarding their data. Ameritrade, Charles Schwab and Vanguard, for example, all said they tried to help their customers, sometimes fully reimbursing them.

"We don't have a policy specifically, but we absolutely help our clients," said Katrina Becker, an Ameritrade spokeswoman. However, she said her company is "definitely considering" a zero-liability policy.

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