The U.S. Department of Justice is launching a probe into possible antitrust violations from four Big Tech companies, Apple Inc., Amazon.com Inc., Facebook Inc. and Alphabet Inc.'s Google, adding to growing competition law concerns for their in-house counsel.

None of the companies have yet taken the 2009 Intel approach—hiring an experienced DOJ antitrust division lawyer as general counsel—but all four have senior counsel or executives with that background. Those lawyers could play a key role in what happens next, though companies did not respond to requests for comment on what competition law work they'll be keeping in-house or if they're growing teams in response to Tuesday's probe launch.

Menlo Park, California-based Facebook is the most recent to publicly beef up its antitrust counsel team. In November the social media company snagged Kate Patchen, the DOJ's top Silicon Valley region antitrust enforcer. Patchen now serves as Facebook's director and associate general counsel of litigation, bringing with her more than a decade of DOJ antitrust experience.

Google also seems to have made recent efforts to up its internal antitrust counsel. The Mountain View, California-based search giant recently sought a competition compliance associate general counsel. In a job posting on LinkedIn, Google listed “experience in compliance and competition/antitrust” as a must.

The company did not respond to questions about the role, which is no longer open to applications. But Google already has an experienced antitrust lawyer on its staff. Washington, D.C.-based Kevin Yingling has served as Google's senior competition counsel for a decade, according to his LinkedIn profile.

Before joining Google in 2009, Yingling spent five years as a trial attorney for the DOJ's antitrust division. He more recently served as counsel for O'Melveny & Myers. Google opted to send Adam Cohen, the director of economic policy who does not have a law background, to testify in a House Judiciary Committee antitrust hearing last week.

Facebook sent head of global policy development Matt Perault, who earned a juris doctor at Harvard in 2008 but does not have any listed antitrust experience, to the hearing. Both Apple and Amazon, the only impacted company not based in California, sent their top in-house antitrust counsel.

For Apple, that's Kyle Andeer, the company's current vice president of corporate law and chief compliance officer. He's been with Cupertino, California-based Apple since 2010, when he joined as a director of competition law. Since then he's moved up the internal antitrust ranks, holding the vice president of competition commercial and international law position before moving into his current role.

Andeer has experience in the DOJ's antitrust division, where he spent nearly four years as a trial attorney, and the Federal Trade Commission. In June, Reuters reported the DOJ and FTC had divided antitrust oversight of Big Tech, with Apple and Google falling under the DOJ's watch.

Facebook and Amazon oversight went to the FTC, according to the report. Seattle-based Amazon's top antitrust in-house lawyer, associate general counsel for competition Nate Sutton, does not have an FTC background but spent more than nine years as a DOJ antitrust division trial attorney.

The representatives from all four companies at last week's hearing argued Big Tech does face competition and does not harm consumers with antitrust practices.

Yet the companies have faced increasing scrutiny at home and abroad. Congress opened a separate probe into Big Tech's possible antitrust violations in June. Last week the European Commission launched a probe into Amazon's competition practices. The commission has hit Google with more than $6 billion in antitrust violation penalties since 2017.

Update: Facebook announced it's facing a separate FTC antitrust investigation Wednesday afternoon.

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