Chinese AI startup DeepSeek's model led to increased scrutiny on Microsoft's AI spending.

"Investing 'very heavily' in capital expenditure and infrastructure is going to be a strategic advantage over time," Mark Zuckerberg said.

Key tech stocks were a mixed bag in early trading Thursday after executives at Meta and Microsoft said they plan to keep pouring billions of dollars into AI – despite lingering anxiety over the launch of China-based DeepSeek’s AI model.