In the unusually public battle, the company that let Cambridge Analytica harvest 87 million users' data is running newspaper ads headlined "Apple vs. the free internet."

The FTC is moving "deeper into the consumer review ecosystem," advertising lawyer Jeff Greenbaum says.

Apple's latest move in a long-running battle over online privacy involves clamping down on a technique that allows ad-tech companies to masquerade as first parties. The ad industry, which opposes Apple's default anti-tracking settings, is criticizing the new canonical name policy.