US software stocks slammed on mounting fears over AI disruption, lose $1 trillion in a week 

Shares of U.S. software and data services companies extended their tumble for a seventh straight session on Thursday as ​investors worried that fast-advancing artificial intelligence tools could upend the sector.

Shares of U.S. software and data services companies extended their tumble for a seventh straight session on Thursday as ​investors worried that fast-advancing artificial intelligence tools could upend the sector. The S&P 500 software and services index dropped ‌4.6%, having shed about $1 trillion in market value since January 28, in a selloff dubbed “software-mageddon.”

Some of the big tech ​names hurt most by the rout included ServiceNow, which fell 7.6%, Salesforce, which slipped 4.7%, and Microsoft, which sank 5%.

“I would classify this as a sell-everything mindset at this point,” said Dave Harrison Smith, chief investment officer and head of technology investing at asset management firm Bailard.

Canada-based Thomson Reuters , which suffered a record one-day plunge earlier this week after investors raised concerns that a new plug-in from Anthropic’s Claude could disrupt its legal business, fell 5.6% despite raising its dividend and reporting fourth-quarter results largely in line with estimates.

The company, which owns the Westlaw legal database and the Reuters news agency, said it was seeing tangible benefits from AI investments.

“The uncertainty around the ​eventual impact of AI means near-term earnings results will be important signals of business resilience, but in many cases insufficient ⁠to disprove the long-term downside risk,” said Ben Snider, Goldman Sachs’ chief U.S. equity strategist.