Bill Ackman’s hedge fund, Pershing Square, takes a new stake in Microsoft, according to multiple reports. The Wall Street Journal and Channel NewsAsia say Ackman describes Microsoft’s valuation as “compelling” and argues the company is underpriced. Seeking Alpha similarly reports that Ackman reveals the new stake and says the valuation is “highly compelling.” The Globe and Mail and Business Standard add that Pershing Square begins building the position in February, after Microsoft’s share price dips. Business Standard reports Ackman frames the investment decision around the recent stock decline and the valuation level. The Wall Street Journal also reports that Ackman plans to disclose the stake in regulatory filings later Friday, indicating the exact size of the position will be made public through those filings. Across the coverage, the common elements are that Pershing Square has taken a stake in Microsoft, Ackman points to valuation as the rationale, and the details are expected to appear in forthcoming regulatory paperwork.