WASHINGTON (Reuters)—Credit agencies will have to disclose more of their ratings history, and banks will have to share data used to rate financial products with all credit agencies, under rules adopted by U.S. regulators on Thursday.

The U.S. Securities and Exchange Commission passed those rules and proposed others as it took aim at the credit rating industry, blamed for fueling the financial crisis by assigning and maintaining high ratings on toxic mortgage-backed securities.

The agency also voted to ask for comment on whether credit agencies should be categorized as "experts" under securities law, and thus subject to tougher standards of liability. The SEC said it is not proposing such a move yet but wants feedback on its potential impact.

Further, the SEC proposed on Thursday to require banks to disclose all preliminary ratings they receive from credit agencies in an attempt to stop banks from shopping for the best credit rating for their products.

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