Credit cards and other financial products would lose their shield from group lawsuits under a potential new rule from the U.S. Consumer Financial Protection Bureau.

The rule would ban "class-action waiver" language in contracts, which blocks consumers from banding together to challenge practices they think are illegal.

"Consumers should not be asked to sign away their legal rights when they open a bank account or credit card," CFPB Director Richard Cordray said in an announcement of the potential rules.

Many financial products -- and other services such as cellphone contracts -- require customers to arbitrate disputes in an out-of-court forum, instead of filing lawsuits. Most such mandatory or "pre-dispute" arbitration language also contains a class-action waiver that blocks customers from taking united action, either in court or group arbitration.

In a March study, the CFPB found relatively few consumers challenged financial companies on their own. But group lawsuits generated refunds for millions of consumers while they deterred harmful corporate practices.

"Companies are using the arbitration clause as a free pass to sidestep the courts and avoid accountability for wrongdoing," Cordray said.

Because arbitration is generally private, companies may continue to profit from a harmful practice even while they compensate individual consumers who complain about it.

While it is taking aim at barriers to group lawsuits, the CFPB is not considering outlawing all arbitration clauses, the outline states.

However, the rule may make information about arbitration claims and awards public, and publish the information on the CFPB website.

The outline of the potential rule released Wednesday will be discussed by a panel of small-business representatives before a formal regulation is proposed. The release of the outline comes the same day that the CFPB held a public hearing on arbitration in Denver.

Supporters of class action waivers at the hearing said they save companies costly and usually unnecessary court battles, thereby reducing prices. Most consumers are able to resolve their disputes informally, and shouldn't have to shoulder the hefty legal bills run up by court battles, they said.

Companies' dispute costs will soar -- consumers will be the losers," said Alan Kaplinsky, a partner at law firm Ballard Spahr who pioneered class action waivers. As a corporate lawyer, Kaplinsky said he's seen how most class action lawsuits are settled with no money going to consumers. "Most of them are meritless," he said. "They are brought by plaintiffs' attorneys with no idea to prosecute the class action, but to extract a settlement and to be paid an attorney's fee."