Even though the subprime market was showing signs of stress , mr. rekeda 's group assembled delphinus in july 2007 , increasing its size to $ 1.6 billion from an initial $ 1.2 billion , citing strong investor demand .
Magnetar hasn 't been accused by regulators of any wrongdoing regarding delphinus , but its role in various mortgage-bond deals has been scrutinized in other sec investigations .