Microsoft's CEO Satya Nadella speaks to participants during the Viva Technologie show at Parc des Expositions Porte de Versailles on May 24, 2018, in Paris.

With the $1 trillion valuation mark now behind Amazon and , two more technology companies are quickly closing in on the milestone.

and are the next biggest companies racing to a $1 trillion market capitalization, each closing in on the mark yet still over $100 billion away. Here's what it would take to get the 10 U.S. companies behind Apple and Amazon to $1 trillion: