Ratings agency DBRS continues to build up its residential mortgage-backed securities ratings space, approving due dilgence firm Clayton Holdings as a third-party reviewer of mortgage bonds.

Shelton, Conn.-based Clayton Holdings provides due diligence reports and underwriting reviews on both residential and commercial mortgages as well as fixed-income securities.

"Clayton is pleased to be one of the first third-party reviewers to be vetted and approved by DBRS," said Paul Bossidy, Clayton's chief executive officer. "When nonagency securitization returns on a broad scale, investors will expect significantly higher levels of transparency, and they will want to know that well-qualified due diligence firms followed well-established protocols in reviewing the quality of the assets backing the securities."

The Financial Crisis Inquiry Commission, formed to investigate the financial fallout, released data and testimony from Clayton officers who said over an 18-month period from 2006 through 2007, the firm performed due diligence on 911,039 loans and found that 39% of the loans it classified as deficient were eventually "waived in" by the banks anyway, according to the FCIC commission testimony.