Fitch Ratings affirmed SL Green Realty Corp.'s issuer default and senior unsecured note ratings at BBB- and its perpetual preferred stock rating at BB, and changed the company's outlook to positive from stable.

The issuer default and certain other ratings of the company's operating partnerships, SL Green Operating Partnership LP and Reckson Operating Partnership LP, were also affirmed.

Fitch said the ratings reflect SL Green's credit strengths, which include its strong competitive edge, high-quality office portfolio in New York, above-average contingent liquidity, limited exposure to floating-rate debt, and well-balanced lease maturity and debt expiration schedules.

The rating agency attributed the positive outlook in large part to SL Green's commitment to maintaining its leverage at 7.0x or below and other stronger financial metric targets.