The sources said Goldman Sachs was advising S&P on the bid.
One analyst said a deal between S&P and MSCI “would make perfect sense”. Referring to last year’s $13 billion deal to merge US analytics firm IHS and London’s Markit, he added: “It surprises me when Markit and IHS got together that nobody immediately moved for MSCI.”
S&P and MSCI said they do not comment on market speculation. Goldman Sachs declined to comment.