Hot in Silicon Valley: Walmart vs Amazon Prime

Walmart takes on Amazon Prime: The retail giant, which last year acquired Amazon competitor Jet.com for $3 billion, is adding free two-day delivery for orders $35 and over and without membership fees (Amazon charges $99 a year).

Competing directly with Amazon is a big challenge. Walmart will now see if consumers prefer to trade membership fees (Walmart previously charged $49 per year) for a minimum order size. In any case, free two-day shipping has become "table stakes" in the online retail wars, said Jet.com co-founder Marc Lore.

Google employees rally for immigration: On Monday, more than 2,000 Alphabet employees gathered to march and rally at various company locations worldwide in protest of Trump's recent immigration executive order. Co-founder Sergei Brin and CEO Sundar Pichai gave speeches at the company's headquarters in Mountain View., Calif.

According to former YouTube executive Hunter Walk, Alphabet employees reached the $2 million mark in donations the morning after the company announced it would match donations to a legal defense fund.