Shares of IHS Markit Ltd. /zigman2/quotes/210124395/composite INFO +1.92% rallied 5.9% in premarket trading Monday, after the information and analytics company announced an agreement to be acquired by S&P Global Inc. /zigman2/quotes/208931849/composite SPGI -0.08% in an all-stock deal that values IHS at about $44 billion, including $4.8 billion in debt. Under financial terms of the deal, S&P Global will exchange 0.2838 shares of its stock for each IHS share outstanding. Based on Friday's stock closing prices, that values IHS shares at $96.94 each, a 4.7% premium. The companies expect annual cost synergies of $480 million, and S&P Global expects the deal to add to earnings by the end of the second full-year after the merger, which is expected to close in the second half of 2021. "This merger increases scale while rounding out our combined capabilities, and accelerates and amplifies our ability to deliver customers the essential intelligence needed to make decisions with conviction," said S&P Global Chief Executive Douglas Peterson. IHS's stock has rallied 22.9% year to date through Friday and S&P Global shares have climbed 25.1%, while the S&P 500 /zigman2/quotes/210599714/realtime SPX -0.72% has gained 12.6%.