(Bloomberg News) The U.S. Commodity Futures Trading Commission proposed limits on banks' proprietary trading and hedge fund investments under the Dodd-Frank Act's Volcker rule.

The CFTC voted 3-2 to propose the ban, becoming the last of five regulators to seek public comment on the proposal. Today's vote opens the measure to 60 days of public comment.

The rule, named for former Federal Reserve Chairman Paul Volcker, was included in Dodd-Frank to rein in risky trading at banks that benefit from federal deposit insurance and Fed discount window borrowing privileges.

The CFTC didn't participate when the Fed, Federal Deposit Insurance Corp., Securities and Exchange Commission and Office of Comptroller of the Currency released a joint proposal last year. Those four agencies extended the comment period on their proposal until Feb. 13 after financial-industry groups and lawmakers cited the complexity of the rule and the lack of coordination with the CFTC in seeking an extension.

The proposed rule would ban banks from making trades for their own accounts while allowing them to continue short-term trades for hedging or market-making. It also would limit banks' investments in private-equity and hedge funds.