A judge’s recent decision favoring AXA Equitable Life Insurance Co. in a lawsuit over excessive mutual fund fees in variable annuities was a win of sorts for insurance companies, in that it upholds a traditional structure of offering investment options.

At issue in the lawsuit, Sivolella v. AXA Equitable Life Insurance Co. et al, is whether the insurer and an RIA subsidiary, which act as investment advisers to mutual funds inside AXA variable annuity contracts, received disproportionally large fees for services rendered to the funds.

Plaintiffs claim AXA delegated investment management responsibility to subadvisers, yet paid those subadvisers only a fraction of the fee, keeping the bulk for itself, despite them performing virtually all fund services.

“This was an attack on the structure for mutual funds used in variable annuities. And that attack failed,” said Mike Isenman, a partner in Goodwin Procter’s securities litigation and SEC enforcement practice.

“It’s a big deal a court is saying the status quo is okay, because if the court had said otherwise, there would have been repercussions,” Mr. Isenman said, adding it would have “sent shockwaves through the industry.”

The AXA case, originally filed in 2011, is the first to be tried in more than six years under section 36(b) of the Investment Company Act of 1940, which gives fund shareholders recourse to recover compensation received by an investment adviser who breached their fiduciary duty to a fund.

Although there have been a number of similar suits that have gone to trial in the past (in which plaintiffs have never prevailed) the AXA case is slightly unique, said Mr. Isenman, a defense attorney.

Whereas in the past, suits have scrutinized costs by comparing proprietary mutual fund fees to those charged by the same adviser to separate accounts, this case is more directly focused on the sub-advised fund itself, according to Robert Skinner, a partner in the securities litigation practice at Ropes & Gray.

The judge who handed down the decision on Aug. 25, Peter Sheridan of the U.S. District Court for the District of New Jersey, said plaintiffs “failed to meet their burden” to demonstrate breach of fiduciary duty on the part of AXA or show “any actual damages.”

The AXA suit was the first to go to trial among approximately 20 pending lawsuits with similar allegations, Mr. Isenman said. Those include companies such as Principal Financial, Voya Financial, New York Life, State Farm, Prudential and The Hartford, as well as non-insurance firms such T. Rowe Price and BlackRock.

The Hartford’s trial is next on the docket, with a trial scheduled for December, according to Mr. Isenman.

Due to the facts-dependent nature of these cases, Mr. Skinner, a defense attorney, cautioned that people should tread lightly when extrapolating from one court decision.

“I think if had gone the other way, people would have certainly paid attention, but it wouldn’t have signaled that fees across the industry were excessive,” he said.

One attorney involved in some of the pending cases, who requested anonymity due to sensitivities regarding ongoing litigation, pointed to one shortfall on the plaintiffs’ side that may be unique to this case, and could have ultimately lost them the trial.

While plaintiffs concretely identified how much sub-advisers to the AXA funds were paid for services, “it remains unclear how much FMG retained in fees,” Judge Sheridan wrote in the opinion. FMG represents AXA subsidiary AXA Equitable Funds Management Group.

That lack of information “makes the Court’s ultimate decision in this case nearly impossible,” he said, because there wasn’t “competent evidence” to determine if fees were excessive relative to services rendered.

Plaintiffs may provide such proof in later litigation and the court will have to grapple with that “key” issue, the anonymous attorney said.

Plaintiffs are planning an appeal, according to their attorney, Robert Lakind of law firm Szaferman, Lakind, Blumstein & Blader. He declined additional comment.