Panel expands Web tracking inquiry

A congressional committee wants the nation’s largest telecommunications and Internet companies to explain whether they target online advertising based on consumers’ search queries and Web surfing habits.

In an expanding inquiry into the state of consumer privacy on the Internet, House Energy and Commerce Committee leaders sent letters Friday to more than 30 companies, demanding to know whether they track where their users go online and use that data to deliver personalized advertising.

Among the companies receiving the letters were Google Inc., Yahoo Inc., Microsoft Corp., AT&T; Inc., Comcast Corp., Qwest Communications International Inc., Verizon Communications Inc. and Time Warner Inc.’s AOL unit. The companies were given a week to respond.

The letters build on an earlier probe by the committee into “deep packet inspection” technologies, which can track where people go online.

The committee already has been investigating Embarq Corp., an Internet service provider in Overland Park, Kan., that has been testing technology to track the online behavior of its customers and then serve up targeted ads based on their presumed interests.

Ari Schwartz, vice president of the Center for Democracy & Technology, a civil liberties group, said he was optimistic that the congressional inquiries could lead to general privacy legislation that would safeguard consumer data.