The Federal Housing Finance Agency ordered Fannie Mae and Freddie Mac to require minimum guaranty fees on their mortgage-backed securities because of concerns about buying market share through pricing. The GSEs were required to charge the same “minimum” guaranty fee for single-family guaranty commitments issued on or after Aug. 1. For 30-year mortgages, the minimum fee is 44 basis points, and it’s 30 bps for 15-year loans, according to documents obtained by Inside MBS & ABS, an affiliated newsletter, under the Freedom of Information Act. The minimum g-fees apply only to Fannie and Freddie swap business and not their cash windows. Inside MBS & ABS estimated that roughly 60 percent of single-family MBS issuance is through swaps.