Group 1: Bill Ackman's Investment Strategy - Billionaire investor Bill Ackman, known for activist short-selling, has shifted to long positions, with his fund, Pershing Square Capital Management, now holding about a dozen stocks [1] - Pershing Square has never owned Tesla but recently launched a new position that has become its largest holding, representing a bet against Tesla for the time being [1] Group 2: Robotaxi Industry Developments - The robotaxi revolution is gaining momentum, with full-self-driving (FSD) capabilities starting to appear in major cities, indicating the industry is at a tipping point [2] - Tesla has initiated its first batch of autonomous robotaxis in Austin, Texas, marking a soft launch, although the vehicles are currently geo-fenced and monitored by humans [4] Group 3: Competitive Landscape between Tesla and Uber - Pershing Square's significant investment in Uber, which constituted 19% of its portfolio at the end of Q1, positions it against Tesla, as both companies are focusing on robotaxis for future growth [5][6] - Analysts believe Tesla's robotaxi initiative poses a long-term threat to Uber's business model, with the potential for a fleet that operates without human labor [6] - Uber is also pursuing partnerships to build a robust network for autonomous vehicles, collaborating with companies like Waymo and Pony.ai [7][8] Group 4: Future Prospects and Valuations - Uber estimates the autonomous opportunity could exceed $1 trillion in the U.S., positioning itself as a key player due to its scale and operational capabilities [8] - Tesla and Uber are currently competitors in the robotaxi space, although there is speculation about potential partnerships in the future [9][10] - Tesla's stock is trading at approximately 170 times forward earnings, reflecting high expectations for its robotaxi business, while Uber trades at 25 times forward earnings, indicating lower expectations for its autonomous initiatives [11]