WASHINGTON—The Justice Department is opening a broad antitrust review into whether dominant technology firms are unlawfully stifling competition, adding a new Washington threat for companies such as Facebook Inc., Google, Amazon.com Inc. and Apple Inc.

The review is geared toward examining the practices of online platforms that dominate internet search, social media and retail services, the department said, confirming the review shortly after The Wall Street Journal reported it.

You Might Like
Learn more about RevenueStripe...