Failed mega-mergers and regulatory uncertainty in the health insurance sector promise to bring additional legal work to law firm practices that are already bustling.

Related: Judge cites 'serious concerns,' blocks Aetna's $37B merger with Humana

As Congress grapples with whether it will ever be able to replace the Affordable Care Act, law firms have a real opportunity to help a broad array of clients in limbo: Insurers are looking to innovate, state health care exchanges face an uncertain future and health care systems continue to eye consolidation. As they await clarity, clients are weighing whether to put new initiatives on hold. And they want a voice in the ultimate outcome — which means that law firm lobbying practices have big role to play, too.

Here, we look at the health insurance industry from the perspectives of law firms, regulators and corporate counsel.

Firms are likely to see increased work across practice areas, including health care, lobbying, antitrust, bankruptcy, and mergers and acquisitions. Much of the work is already underway, while litigation only promises to grow as the regulatory framework is adjusted.

Recent months have seen high billings by antitrust lawyers in particular, and that work is expected to continue as insurers say they will appeal court rulings rejecting several large-scale mergers. Jones Day and Crowell & Moring represented Aetna Inc. and Humana Inc., respectively, in their unsuccessful merger attempt.

White & Case represented Anthem Inc. in its bid to merge with Cigna Corp., which tapped Charles “Rick” Rule of Cadwalader, Wickersham & Taft; midway through the matter, Rule switched to Paul, Weiss, Rifkind, Wharton & Garrison. Neither deal has passed muster in the courts’ eyes. Aetna abandoned its planned purchase of Humana. Anthem is appealing its case, while Cigna announced plans to sue Anthem for alleged breaches of the merger agreement.

Meanwhile, Drinker Biddle & Reath and Hogan Lovells represented Advocate Health Care in its failed bid to merge with NorthShore University HealthSystem in Chicago, represented by Winston & Strawn. The companies decided in March to end their efforts to push the merger forward.

Boies Schiller Flexner and Hausfeld continue to lead a fight by a group of health insurers in antitrust litigation against Blue Cross Blue Shield Association and dozens of member health plans in multidistrict litigation in Alabama. Kirkland & Ellis is representing the defendants in the litigation, which claims subscribers paid more because of the defendants’ alleged anti-competitive conduct.

Insurance companies continue to face lawsuits over pricing. Matthew Cantor of Constantine Cannon is representing the plan-member plaintiffs in an antitrust suit against Sutter Health, defended by Jones Day. That putative class action was revived by the U.S. Court of Appeals for the Ninth Circuit last year.

Related: Blocking Anthem-Cigna merger, judge says internal discord didn't help deal

Cantor says he expects consolidation in the health insurance industry to continue despite the high-profile failure of the Aetna-Humana and Cigna-Anthem deals, and consolidation among providers will lead to more litigation with insurers, he predicts. “There will be continued fights between providers and health insurers,” he says. “Providers are, in many areas of the country, getting very, very big, and insurers are trying to push back on those providers.”

David Deaton, co-chair of O’Melveny & Myers’ broad-based health care and life sciences practice, says he has seen a shift in health care-related government investigations, with qui tam cases moving away from pharmaceutical companies and hospitals toward the managed care industry.

The nonprofit, state-chartered co-ops created by the ACA have faced significant troubles, with more than half of the 23 filing for bankruptcy. Douglas Schmidt of Husch Blackwell in Kansas City, Missouri, represented the liquidator in the first bankruptcy of an ACA-formed health insurance exchange. He has worked alongside lawyers at Faegre Baker Daniels, which represents the National Organization of Life and Health Insurance Guaranty Associations, to handle many more since.

Schmidt says the “three Rs” of the ACA — risk adjustment, reinsurance and risk corridors — have kept insurance lawyers busy. While reinsurance and risk corridors sunset after three years, risk adjustment continues to provide reimbursements to insurers who take on high-risk subscribers. Schmidt said the industry is likely to see litigation over how any potential repeal of the ACA could impact payments insurers will say they are owed.

McDermott Will & Emery has doubled down on the health insurance industry, says chair Ira Coleman, and expects it to be a big driver of work in the coming few years. While some firms handle a specific facet of health care-related work, McDermott takes an industrywide approach, handling litigation, government investigations, M&A and related matters.

“You just took a $3 trillion health care industry and you just shook it up, so there is going to be a lot of changes,” Coleman has said. “There is a lot of unknown and uncertainty and we are going to help our clients figure this all out.”

The regulatory climate

Just as the health care industry was digesting the details of the Republican plan to repeal Obamacare that was announced on March 6, the proposal was withdrawn on March 24 when there weren’t enough votes for it to make it through the U.S. House of Representatives.

Related: Making the case for health insurance mergers

K Royal, vice-chair of the Association of Corporate Counsel’s health law committee, spoke with The American Lawyer in advance of that withdrawal, and her comments turned out to be right on target.

Royal had said the arguably controversial provisions of the plan — such as a proposal to increase by 30 percent the premiums of people who let their insurance lapse — might delay passage of the bill by a year or longer. And then there was the issue of how much the plan would cost, which had not been specified.

“Someone needs to put in there how they’re going to pay for it,” Royal, a former privacy counsel at San Jose, California-based Align Technology Inc, had said. “People complain about having high deductibles now, but under this, they’re going to have to pay for everything, and I don’t see where this plan can fix that at all.”

Health care attorneys also are keeping a close eye on additional rulemaking in 2017 associated with the Medicare Access and CHIP Reauthorization Act of 2015, or MACRA, which imposes substantial changes to how Medicare pays for physician services. Under the law, Medicare pays doctors based on their performance, rewarding them for higher-quality work, rather than paying them in accordance with a fee schedule.

“It’s a game-changer that continues a policy trend toward linking payment with performance,” says Eric Zimmerman, a partner at McDermott Will, who heads the firm’s health industry advisory practice group.

The in-house take

General counsel at health care companies have been in a wait-and-see mode, watching to see what the fate of the ACA will be, and what might replace it. “The uncertainty is the No. 1 topic,” says Lawrence Lopardo, executive vice president and general counsel at Oregon-based Avamere Health Services, headquartered in Wilsonville, Oregon, a group of independent companies that provide skilled nursing, assisted living, therapy, home health and hospice to senior citizens in several Western states. “When there’s uncertainty, you tend to not do new things,” he adds.

But Lopardo and others say that the industry has a chance to have its voice heard while the health care system is under review by an administration that has vowed to reduce regulations. “We as a profession certainly see an opportunity to put forth ideas to the decision-makers in Congress and the administration about what those decreased regulations would be,” Lopardo says.

Bill Dombi, vice president for law at the National Association for Home Care & Hospice in Washington, D.C., likewise cites the potential decrease in regulation as an antidote to the worries that keep him awake at night. He points to an unpopular home health regulation that, similar to the system of prior authorization under commercial insurance plans, would require Medicare pre-claim review. Late last year, then-Rep. Tom Price, now the new secretary of Health and Human Services, introduced legislation that would halt the program.

“There is hope that the Trump administration will put a pause on this shotgun approach to regulation,” Dombi says. “We don’t expect with Trump and Price in office that oversight is going to go away entirely — that would be bad business — but we’re hopeful we can take a more sensible approach to it.”

For their part, private insurers share this excitement over the possibility of less government restriction and oversight but are less worried about the uncertainty, outside lawyers who represent the companies say. “They have long-term strategy plans that they think they can execute well regardless of the administration,” Nelson Hardiman’s Fuller says.

Amid the uncertainty, there has been movement among in-house lawyers at health care organizations. The American Medical Association announced Feb. 28 the appointment of Brian Vandenberg as senior vice president and general counsel. Vandenberg most recently served as general counsel at Livongo Health Inc., a consumer digital health company in Mountain View, California. He replaces Jon Ekdahl, who is retiring after almost 16 years with the AMA.

In the lead-up to the trials over the insurance company mergers, one health care attorney notes there were a number of in-house attorneys who made moves or started to put their resumes out, as the future of their legal departments were in question.