NEW YORK--(BUSINESS WIRE)--Fitch Ratings has assigned an 'AA-' rating to Massachusetts Mutual Life Insurance Company's (MassMutual) $500 million 4.50% surplus notes due in 2065. MassMutual's Long-term Issuer Default Rating is not affected by this rating action. MassMutual's Rating Outlook is Stable. On Feb. 23, 2015, Fitch affirmed the ratings of MassMutual and its insurance operating subsidiaries with a Stable Outlook. KEY RATING DRIVERS The ratings are equivalent to the ratings assigned to Ma