Almost $1 trillion has been erased from the value of Wall Street’s largest technology companies this week, as investors grow increasingly wary of soaring valuations linked to artificial intelligence.
The so-called Magnificent Seven — Nvidia, Tesla, Alphabet, Amazon, Meta, Microsoft and Apple — have borne the brunt of the sell-off, which traders say reflects mounting scepticism over whether AI investment enthusiasm is justified by underlying profits.
Nvidia, which last month became the world’s first $5 trillion company, fell a further 2.3% in early New York trading and has shed nearly $500 billion in market value this week alone.
Collectively, losses across the Magnificent Seven have reached $953.7 billion (£724.5 billion). The Nasdaq Composite, the world’s leading tech index, is heading for its worst week since Donald Trump’s April tariff onslaught, down 3.9% so far.
The sell-off comes as traders question whether AI firms’ ambitious spending plans can be supported by revenue growth. OpenAI’s $1.4 trillion, eight-year investment blueprint, underpinned by a $100 billion partnership with Nvidia, has underscored concerns about the scale of capital being deployed relative to earnings.
Sam Stovall, chief investment strategist at CFRA Research, said:
“There is a continuation of concern about a possible pullback — it’s traditional early-November weakness triggered by elevated valuations and a lack of fresh catalysts to support the market.”

