OLDWICK, N.J.–(BUSINESS WIRE)–A.M. Best has assigned a Long-Term Issue Credit rating of “aa-” to the $475 million 4.9% surplus notes issued March 20, 2017, with a maturity of April 1, 2077, issued by Massachusetts Mutual Life Insurance Company (MassMutual) (Springfield, MA). The outlook assigned to this Credit Rating (rating) is stable. The proceeds of the sale of the newly issued surplus notes will be used to repurchase existing outstanding surplus notes through a tender offering. As the pro