(Bloomberg) -- BlackRock Inc.’s Laurence D. Fink, whose firm is the largest shareholder in companies from Apple Inc. to JPMorgan Chase & Co., is repeating his call to chief executive officers to engage with shareholders and be more transparent about balance-sheet decisions.

Following up on a January 2012 letter in which he urged 600 of BlackRock’s largest holdings to adopt shareholder-friendly practices, Fink wrote last week to the heads of all companies in the Standard & Poor’s 500 Index, asking them to focus on sustainable returns and not give in to short-term pressures.

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