Microsoft Corp.'s MSFT, -1.24% new reign as the most valuable U.S. company by market capitalization is in danger to end after just two days, as the stock slumped 0.7% while Apple Inc. shares AAPL, -3.17% rallied 1.0%. The moves boosted Apple's market cap to $1.413 trillion from $1.398 trillion at Tuesday's close, and knocked Microsoft's market cap down to $1.393 trillion from $1.403 trillion. Microsoft overtook Apple on Monday, after a 70-session stretch in which Apple was No. 1. The technology behemoths' market caps are still well above No. 3 Amazon.com Inc. AMZN, -1.78% at $1.081 trillion and Google-parent Alphabet Inc. GOOGL, -2.41% at $1.039 trillion. Shares of Apple have rallied 23.3% over the past three months toward a record close Wednesday, while Microsoft has hiked up 24.6% and closed at a record on Monday. In comparison, the Dow Jones Industrial Average DJIA, -0.87% was up 206 points, and has gained 6.5% over the past three months, and was on track for a record close on Wednesday.