OREANDA-NEWS. April 28, 2015. Fitch Ratings has affirmed the ratings for the class A and B notes issued by SLM Student Loan Trust 2007-4 at 'AAAsf' and 'Asf', respectively. The Outlook is Stable for all notes. A full list of ratings follows at the end of this release.

KEY RATING DRIVERS

High Collateral Quality: The trust collateral consists of 100% of Federal Family Education Loan Program (FFELP) loans. The credit quality of the trust collateral is high, in Fitch's opinion, based on the guarantees provided by the transaction's eligible guarantors and reinsurance provided by the U.S. Department of Education (ED) for at least 97% of principal and accrued interest. The current U.S. sovereign rating is at 'AAA' with a Stable Outlook.

Sufficient Credit Enhancement: While both the senior and subordinate notes will benefit from future excess spread, the senior notes also benefit from subordination provided by the class B notes. As of December 2014, total parity is 100.00% and senior parity is 104.46%. The trust is releasing cash given that the 100% total parity is maintained.

Adequate Liquidity Support: Liquidity support is provided by a reserve account. The reserve is sized equal to the greater of 0.25% of the pool balance, and \\$ 7,500,000.

Acceptable Servicing Capabilities: Navient Solutions, Inc. (formerly known as Sallie Mae, Inc.), as servicer, will be responsible for servicing the portfolio. Fitch believes that Navient Solutions is an acceptable servicer of FFELP student loans.

RATING SENSITIVITIES

Since FFELP student loan ABS rely on the U.S. government to reimburse defaults, 'AAAsf' FFELP ABS ratings will likely move in tandem with the 'AAA' U.S. sovereign rating. Aside from the U.S. sovereign rating, defaults and basis risk account for the majority of the risk embedded in FFELP student loan transactions. Additional defaults and basis shock beyond Fitch's published stresses could result in future downgrades. Likewise, a buildup of credit enhancement driven by positive excess spread given favorable basis factor conditions could lead to future upgrades.

Fitch has affirmed the following:

SLM Student Loan Trust Series 2007-4:
--Class A-4A at 'AAAsf'; Outlook Stable
--Class A-4B at 'AAAsf'; Outlook Stable
--Class A-5 at 'AAAsf'; Outlook Stable
--Class B-1 at 'Asf'; Outlook Stable
--Class B-2A at 'Asf'; Outlook Stable
--Class B-2B at 'Asf'; Outlook Stable