NEW YORK — Bank of America, the lender burdened by its Countrywide Financial Corp. takeover, would consider putting the unit into bankruptcy if litigation losses threaten to cripple the parent, said four people with knowledge of the firm’s strategy.

The option of seeking court protection exists because the Charlotte, N.C.-based bank maintained a separate legal identity for the subprime lender after the 2008 acquisition, said the people, who declined to be identified because the plans are private. A filing isn’t imminent and executives recognize the danger that it could backfire by casting doubt on the financial strength of the largest U.S. bank, the people said.

The threat of a Countrywide bankruptcy is a “nuclear” option that Chief Executive Officer Brian Moynihan could use as leverage against plaintiffs seeking refunds on bad mortgages, said analyst Mike Mayo of Credit Agricole Securities USA. Moynihan has booked at least $30 billion of costs for faulty home loans, most sold by Countrywide during the housing boom, and analysts estimate the total could double in coming years.

“If the losses become so great, how can Bank of America at least not discuss internally the relative tradeoff of a Countrywide bankruptcy?” Mayo said in an interview. “And if you pull out the bazooka, you’d better be prepared to use it.”

Just before former CEO Kenneth Lewis bought Calabasas, Calif.-based Countrywide, the firm was the biggest mortgage lender in the United States with 17 percent of the market and $408 billion of loans originated in 2007, according to industry newsletter Inside Mortgage Finance. Regulators later found its growth was fueled by lax lending standards, with loans marred by false or missing data about borrowers and properties.

Bankruptcy for Countrywide has gained credence with some investors and analysts after Bank of America lost almost half its market value this year. The shares have been whipsawed as the caseload of lawsuits by mortgage bond investors expanded, along with doubts about whether the bank has enough reserves to handle claims.

A Countrywide bankruptcy could halt legal proceedings and consolidate litigation into one court that would split up the subsidiary’s remaining assets for creditors, said Jay Westbrook, a law professor at the University of Texas at Austin. In effect, this would trade one type of litigation for another, one of the people said. The decision would turn on whether the potential savings of a filing outweigh the risks involved in disavowing some of the firm’s obligations, the person said.

Pitfalls include the possibility that a bankruptcy filing would cast doubt on the entire company’s willingness to support its other subsidiaries and damage Bank of America’s standing in the credit markets or with rating firms, hurting its ability to borrow, according to analysts.

“It’s not some sort of magic elixir that makes it all just go away,” Westbrook said. “I suspect that’s one reason they haven’t done it yet.”

Moynihan, 51, has been asked publicly about a potential Countrywide bankruptcy at least three times in the past year, most recently this week at a conference in New York. The bank’s mortgage division is his only unprofitable business, reporting a $25.3 billion pretax loss in the first half of this year.

Larry DiRita, a Bank of America spokesman, said he couldn’t comment on whether the company planned to file a Countrywide bankruptcy. The bank “took great pains to preserve the separate identity of Countrywide,” DiRita said.

Those steps include using separate accounting systems and profit-and-loss statements for Countrywide units, according to a report prepared for Bank of New York Mellon Corp., the trustee for a group of investors who agreed to an $8.5 billion settlement in June with Bank of America over faulty loans.

Bankruptcy “makes absolute good sense if they can do that,” said David Felt, a Washington-based consultant and former deputy general counsel at the Federal Housing Finance Agency. The FHFA sued Bank of America and 16 other banks this month to recover losses on about $200 billion in mortgage-backed securities sold to Fannie Mae and Freddie Mae, the government- backed mortgage firms. Bank of America and its subsidiaries created more than a quarter of those bonds.