NEW YORK--(BUSINESS WIRE)--Kirby McInerney LLP is investigating potential claims against the Board of Directors of Navient Corporation (“Navient” or the “Company”) (NASDAQ:NAVI) for possible breaches of fiduciary duty and other violations of federal securities law. On July 13, 2015 the Company announced a substantial cut to its prior financial guidance for the remainder of its 2015 annual performance. The Company now expects second-quarter core earnings of $0.40 per share, and full-year 2015 co