complying with paragraph (1), each enterprise undertake multiple types of the various transactions and structures described in subsection (b). (b) Types of transactions The risk-sharing transactions referred to in subsection (a) may include transactions involving increased mortgage insurance requirements, credit-linked notes and securities, senior and subordinated security structures, and such other structures and transactions as the Director considers appropriate to increase private market assumption of credit risk. . 106. Limitation of enterprise mortgage purchases to qualified mortgages (a) Fannie Mae Section 302(b) of the Federal National Mortgage Association Charter Act ( 12 U.S.C. 1717(b) ) is amended by adding at the end the following new paragraph: (7) Effective for mortgages with application dates on or after January 10, 2019, the corporation may only purchase, make commitments to purchase, service, sell, lend on the security of, or otherwise deal in a mortgage that is a qualified mortgage (as such term is defined in section 129C(b) of the Truth in Lending Act ( 15 U.S.C. 1639c(b)