Bank of America Corp.’s Merrill Lynch was fined $6 million by the Financial Industry Regulatory Authority for allowing short-sellers to dump stocks without making sure they had first arranged to borrow the shares.

The industry-financed regulator levied the fines for breaking rules related to short-selling, or selling a stock with the hope of profiting by buying it later at a lower price. Between 2008 and 2012, Merrill Lynch’s broker-dealer and clearing units violated the Securities and Exchange Commission’s Regulation SHO, which is intended to ensure short-sellers borrow the stock they’re selling, Finra said today in a statement.

Merrill Lynch also violated the SEC’s 2008 emergency orders intended to prevent manipulation of bank stocks, Finra said. The group fined Credit Suisse Group AG and UBS AG for violations related to Regulation SHO in 2011.

“We take very seriously our obligations and have improved our procedures to address issues identified by Finra,” Bill Halldin, a spokesman for Charlotte, North Carolina-based Bank of America, said in an e-mailed statement.

During the financial crisis, Lehman Brothers Holdings Inc. Chief Executive Officer Richard Fuld blamed speculators for the investment bank’s collapse and the SEC investigated short- selling abuses. A later report by Lehman’s bankruptcy examiner found that the bank used off-balance-sheet transactions to understate its leverage.