By the end of Thursday, the company's total stock market value had fallen to $3.46 trillion from $3.97 trillion the day before, hitting a six-month low that spooked investors. Google-owner Alphabet lost just over $500bn in value on Thursday after it revealed that its own artificial intelligence search summaries were hitting search advertising revenue.
Usually lower spending and growing sales earns a positive reaction from investors, but investors appeared dismayed at the impacts these spending plans are having on the ability of each company to keep growing their core lines of business.
Microsoft and Amazon also issued updates this week, and joined Google in plans to keep spending huge sums of cash in the ongoing AI race.
Alphabet also revealed earlier this week plans to cut thousands of workers, which will further reduce the company's costs.
Google-owner Alphabet lost just over $500bn (£374bn) in value on Thursday after it revealed its own artificial intelligence (AI) summaries were hitting search advertising revenue.
In its results published on Wednesday, Alphabet revealed that total revenue grew 25% in the three months to the end of September, compared to the same period last year, hitting $127.6bn.
Google spooked investors so badly that its stock hit a six-month low, after it revealed its AI own search summaries were affecting ad revenue.
Alongside quarterly sales growth of 11%, hitting $201bn, the company shared a staggering cash flow figure of negative $42bn.