The group of servicers handled $1.51 trillion of jumbos at the end of June, up 0.7% from the end of March.

Over the last five years, the share of non-U.S. citizens in the non-agency mortgage-backed security market more than doubled.

"We launched an interest only mortgage product to fill in the market gap left by First Republic [Bank] and others," said Richard Raffetto, a senior executive vice president at Flagstar and president of commercial and private banking.

The planned $560.4 million issuance is the largest CES securitization yet from the nonbank, which started issuing deals in April.

The largest securitization in the batch is a $654.4 million prime non-agency MBS with loans originated by JPMorgan Chase Bank.

The top five jumbo producers in the first half were all federally insured depositories.

Nonconforming products accounted for 21.2% of first-lien originations in the second quarter, according to a new analysis by Inside Mortgage Finance.

Knock and Arixa separately issued their inaugural securitizations, with strong demand from investors.

UWM contributed to three non-agency MBS that started marketing Thursday.

PennyMac Loan Services accounted for 40.8% of the planned $356.1 million issuance, followed by Rocket Mortgage with a 32.8% share and Newrez with a 24.2% share.