Uber Stock Skids, Homebuilding Sector Slips; Workday Jumps

• Shares of ridesharing giant Uber fell on Wednesday, Sept. 17, 2025, after a competitor announcement, while a stake from an activist investor helped boost HR software firm Workday.

• Uber declined 5% after rival Lyft and self-driving technology partner announced a plan to launch robotaxi services in Nashville.

• Workday advanced after Elliott Investment Management said it had accumulated a major position in the enterprise software company.

A big mobility and food-delivery player came under pressure after a competitor announced an expansion of its robotaxi partnership, while a cloud-based business software provider soared after an activist investment firm announced a stake.

The S&P 500 ended Wednesday with a loss of about 0.1% as the Federal Reserve announced a widely expected quarter-percentage-point reduction to benchmark interest rates and suggested that additional cuts could be approaching. The Nasdaq was down 0.3%, while the Dow added 0.6%. Read Investopedia’s full roundup of today’s market activity.

Stocks with exposure to the home building sector lost ground. Although the Fed’s interest-rate cut and outlook promoted expectations that declining mortgage rates could bolster the housing market, the latest data from the The National Association of Home Builders/Wells Fargo Housing Market Index showed that home builder confidence in September remained mired at at its lowest level since December 2022. Shares of residential construction material provider Builders FirstSource (BLDR) lost 5.6%, the most of any S&P 500 stock, while flooring specialist Mohawk Industries (MHK) sank 4%.

Uber Technologies (UBER) shares dropped 5%. The downshift for the ridesharing and food delivery giant came after Waymo, the self-driving technology subsidiary of Google parent Alphabet (GOOG, GOOGL), said it would partner with Lyft (LYFT) to offer fully autonomous rides starting next year. Lyft shares surged more than 13% following the announcement.

Insulet (PODD) shares fell 3%. The maker of wearable insulin delivery devices said that Ana Maria Chadwick would step down from her role as chief financial officer at the end of the month, set to be replaced by a former Charles River Laboratories (CRL) executive. The company said it now expects third-quarter revenue growth to exceed prior expectations, citing strong customer additions in the U.S. and other markets.

Shares of Hologic (HOLX), a medical technology company focused on women’s health, jumped 7.7% to notch Wednesday’s top performance in the S&P 500. The push higher followed reports that investment firms Blackstone and TPG have reinitiated conversations with Hologic’s board about a potential acquisition.