NEW YORK (BLOOMBERG, REUTERS) - PNC Financial Services Group will sell its stake in BlackRock Inc, more than two decades after it bet on the business that became the world's largest asset manager. PNC will exit its investment, worth about US$17.3 billion (S$24.5 billion), with a public secondary offering, it said on Monday (May 11). As part of the transaction, BlackRock will buy back US$1.1 billion of the shares directly from the firm. PNC holds 22 per cent of BlackRock's outstanding shares, making it the largest holder. The separation comes 25 years after P...