Taxpayer Privacy Drives New Focus on Meta, Google Data Tracking

Congressional scrutiny of taxpayers’ data privacy has spawned the latest debate over the use of online trackers created by tech companies like Alphabet Inc.'s Google and Meta Platforms, Inc., increasing the risk of litigation for businesses that deploy them.

Hundreds of thousands of websites are embedded with what’s known as “pixel” technology, according to a recent privacy industry report. Those bits of computer code allow companies to track users’ interactions with their websites, which in turn inform targeted advertising efforts.

But over the last year, these online trackers have sparked hundreds of lawsuits accusing businesses—particularly in health care and ...