Check out the companies making the biggest moves in midday trading: Microsoft — Shares rose nearly 4% after Pershing Square’s Bill Ackman said he has been accumulating stock in the software company since its the stock fell in the wake of its second-quarter earnings report. The hedge fund manger disclosed the investment, but not its size, in a lengthy post on Friday ahead of his company’s quarterly 13F filing. He argued its valuation was “highly compelling.” ServiceNow — The AI platform’s stock rose nearly 5% after the company struck a multiyear partnership with Experian. The companies plan to work together on developing autonomous AI agents. Ford — Shares fell about 7% after the automaker’s stock popped more than 20% in recent sessions as investors caught on to its battery storage ambitions tied to the broader AI trade . Analysts on Friday said recent gains appear driven more by enthusiasm around the planned business than to any near-term fundamentals. RBC analysts estimated…