Fears of Big Tech scrutiny hit Wall Street

The tech-focused Nasdaq Composite closed 1.6% lower on Monday — now 10% from the index's record high — as reports about heightened antitrust scrutiny for Apple, Facebook, Amazon and Alphabet hit those companies' share prices.

Why it matters: Big Tech companies have been the portfolio darlings for investors and hedge funds. Until recently, any threat of regulation in the U.S. was largely ignored by Wall Street, but that may be changing.

• Shares of Apple closed down 1%, while Amazon fell 4%. Alphabet dropped 6%, and Facebook fell more than 7%.