Amazon founder Jeff Bezos is planning to sell nearly 5bn worth of shares in the technology giant, a regulatory filing showed. The planned sale by the world's second-richest person comes as Amazon's stock surged to an all-time high, putting it in an exclusive club of companies with a 2 trillion valuation. The proposed sale of 25 million shares was disclosed in a notice filed after market hours on Tuesday when the stock price climbed to 200.43. That marks a 30 percent jump from the beginning of the year, far outpacing the 4 percent average gain in the Dow Jones Industrial Average index. Once it goes through, Bezos would own about 912 million Amazon shares, or 8.8 percent of the outstanding stock.

For its inaugural re:Mars conference, Amazon invited attendees it calls "dreamers and builders" -- business leaders, scientists and others who are making contributions to the field of artificial intelligence and machine learning. During the Wednesday keynote at the Las Vegas event, Amazon brandished its own AI credentials, making the case to its potential customers and partners that its teams -- across the business -- are pushing forward the stat of the art. Across every step of its e-commerce operations, AI is at work: Amazon shared the way it uses AI to power e-commerce forecasting, and it showcased StyleSnap, an AI-powered feature that lets shoppers in the Amazon app takes a picture of a piece of clothing and find similar items for sale. Amazon also revealed newest fulfillment center robots, called Pegasus and Xanthus, as well as a new drone that Amazon says will start commercial deliveries within months. For in-store shopping, Amazon revealed new details about the technology that drives its Amazon Go stores.