The FTC and DOJ are picking their battles wisely – both agencies’ credentials have been restored – maintaining this momentum is necessary for long term antitrust policy

This new circle of advisers — which now included a supportive Slaughter — helped Khan grow into the job. She became more willing to trust the recommendations of staff attorneys and economists as they developed a better understanding of her vision. She became more selective in the cases and investigations she ordered. Most significantly, she came to understand that while transforming antitrust law required bringing cases that the agency might lose, it was also important to win some to maintain the agency’s credibility and morale. The latest employee satisfaction survey, in fact, shows that the FTC has reversed more than half of its precipitous decline.

Khan’s more pragmatic approach was evident last September when the FTC, along with 17 state attorneys general, filed a much-anticipated suit against Amazon. The 172-page complaint did not rely on many of the novel legal theories Khan had advanced in her star-making article. Instead, it took the more traditional approach, accusing Amazon of raising prices for consumers by punishing third-party sellers on its platform who offered lower prices elsewhere, and by requiring sellers to use Amazon’s expensive fulfillment services to qualify for Prime status.

“She has come to appreciate that being revolutionary at times requires being evolutionary,” said Bill Baer, who was a top official at both the FTC and Justice.

Khan’s adaptability has put some important wins on the board for her agency. For example, rather than pursuing a court battle to block Amgen’s $28 billion purchase of a hot biotech firm, she agreed to settle the case on terms favorable to the FTC. And on appeal, the agency succeeded in unwinding a high-profile biotech merger of firms Illumina and Grail, setting an important new precedent for vertical mergers.

For the first time, the FTC sued a private equity fund, challenging the industry’s appetite for creating virtual monopolies. In this case, a fund had bought nearly every anesthesiology practice in Texas. Judging from the howls of protest from Wall Street, the suit poses a significant threat to the hugely profitable business model of “rolling up” small firms in often-overlooked markets.

And earlier this year, the FTC won an early round of a case brought against two of the largest makers of farm pesticides for using loyalty programs and exclusive contracts to fend off makers of cheaper generic products. If successful, the precedent would implicate business practices widely used in other industries.

At the Justice Department, meanwhile, Kanter’s antitrust division has also been on a roll. Penguin Random House’s purchase of publishing rival Simon & Schuster was blocked on the theory that the combination would lower advances for authors and reduce the diversity of opinions on which democracy depends. Justice also blocked JetBlue’s joint marketing agreement with American Airlines and its purchase of upstart rival Spirit. Based on preliminary rulings, Justice also appears to have the wind at its back in two monopolization cases against Google that seek to break up the internet giant. In March, Justice joined 15 states and the District of Columbia in filing a sweeping suit against Apple over business practices that discourage customers from switching to other phones and using rival apps.

Even so, the biggest win for the hipsters might be a new set of merger guidelines that lay out how the FTC and the Justice Department — and, indirectly, the courts — will interpret and enforce antitrust law. At Khan’s urging, the initial draft of the guidelines abandoned the old Chicago rubric of consumer welfare in favor of hard limits on concentration, relying on reanimated precedents like Von’s Grocery. Laced with questionable economics and movement rhetoric, the draft was widely panned by the antitrust establishment and denounced by business groups.

But after considering thousands of public comments and consulting the priesthood, Khan and Kanter ultimately settled on a set of credible enforcement principles based on updated economics and legal doctrine respectful of precedent but not shackled by it. Under the new rubric, merger reviews will shift from endless arm-wrestling over defining the relevant market and estimating future prices to an inquiry into how firms in that market actually compete. Consumer prices will be a factor in that assessment, but not the only one.