An asset manager working in areas from which banks have pulled out in recent years following the GFC has been acquired.

Western Asset, the fund manager that is part of US-listed Legg Mason, has bought a minority stake in alternative investment house Flat Rock Global, for an undisclosed sum.

The acquirer, which had $429 billion in assets under management as at the end of June, has bought a firm that that develops yield-driven investment strategies focused on asset classes deemphasized by the banking sector. Flat Rock Global exclusively offers its funds through registered investment advisors (RIAs), family offices and institutional investors with a single institutional style share class.

John Thomson of Thomson Equity also invested alongside Western Asset. The investment supports Flat Rock Global's investment strategies, including its initial fund, Flat Rock Capital Corp., a business development company focused on investing in first lien, floating-rate debt of middle-market companies, a statement from the firm said. 

"We are pleased to partner with Western Asset, one of world's premier asset managers," said Robert Grunewald, chief executive and founder of Flat Rock Global. Grunewald said he sees opportunity for alternative debt providers: "With banks receding from middle market lending, private lenders will benefit from demand for growth capital."