The company believes delivering loans to agency MBS helps it be a “high velocity, capital light and cash generating” operation. This year, the firm has held mortgages on its balance sheet for as few as eight days.

Nomura analyst Matthew Howlett says PennyMac's strong performance is a sign of boom times for mortgage lenders. He expects four or five IPOs of nonbank originators in the next nine to 12 months.

Coming off a decent first quarter, Invitation Homes was able to raise almost $400 million through an additional offering of common.