Manhattan Bancorp, the holding company for Bank of Manhattan in El Segundo, announced Wednesday it has completed its investment in a startup mortgage brokerage run by three former Countrywide executives.

The operation, known as Banc of Manhattan Capital, or BOM Capital, is a mortgage broker/dealer focused on institutional fixed-income trading. In the future, BOM may try to originate residential mortgages, according to a Manhattan Bancorp filing with the Securities and Exchange Commission.

The company was created in February by Greg Jacobson, Harold Hermelee and Tad Dahlke, three former executives at Countrywide Financial in Thousand Oaks, which was purchased by Bank of America in January 2008.

The trio started the company with the understanding that Bank of Manhattan would buy a 70 percent stake for $790,000, according to previous filings. That transaction was completed Oct. 1, according to Wednesday’s filing.

The three founders and other employees of BOM Capital will retain 30 percent ownership in the company.

“We are thrilled to close this transaction and be working with the BOM Capital team,” Kyle Ransford. Manhattan Bancorp’s chairman, said in a statement. “Manhattan is looking forward to growing the capital markets sector of our business, and we see the BOM Capital team as an integral part of our success.”

Shares of Manhattan Bancorp fell 25 cents, or almost 4 percent, to end the day at $6.25 per share in over-the-counter trading.