Sprint Corp and its Centel Capital Corp unit have found favour with Standard & Poor’s Corp, which upgraded their senior unsecured debt ratings to triple-B from triple-B-minus; the commercial paper rating of Sprint was raised to A-2 from A-3 and the preferred stock rating to triple-B-minus from double-B-plus, the agency said. About $1,200m of outstanding long-term debt is affected. The ratings upgrades reflect the strengthening financial performance of the company’s long distance telephone operations, and the rating outlook for the company is stable, the New York agency declared.