Gov. Janet Mills has signed a bill that aims to prevent price gouging on tickets for concerts and theater.

LD 913 requires ticket sellers to clearly disclose all fees upfront. It also bans the use of bots to bypass ticket limits and fake websites that mimic real venues. It prohibits vendors from selling speculative tickets — tickets they don’t already own or that haven’t gone on sale yet — and requires resellers to issue refunds for counterfeit tickets. And it says resellers cannot add more than 10% to the original price of the ticket, including taxes and fees.

Tony Ronzio, a spokesperson for Mills, did not share an explanation Friday when asked why the governor decided to support the bill. It will take effect 90 days after the Legislature adjourns — a date still to be determined.

Local performing arts organizations, theater groups and concert venues had supported the bill. They told stories about patrons who paid much more than face value for their tickets on duplicated websites or even showed up to concerts only to learn that their tickets were fake.

“It just is really about keeping our creative economy dollars circulating locally,” Mollie Cashwell, director of the Cultural Alliance of Maine, said earlier this month when the Maine Legislature passed it.

Opponents included StubHub, a popular resale website, and advocacy groups such as the Sports Fans Coalition and the National Consumers League.

“By passing LD 913, Maine leaders rewarded the Live Nation-Ticketmaster monopoly while putting fans at risk,” Dave Garriepy, senior government affairs manager at StubHub, said a written statement. “This bill not only endorses Ticketmaster’s restrictive and opaque practices, it slaps on artificial price caps that will drive buyers to unsafe, unregulated sites where scams flourish. It’s disappointing lawmakers ignored consumer advocates and the clear third-party evidence warning price caps will lead to widespread fraud. We urge the state to rethink this law to protect Maine fans.”

Once the bill takes effect, the Maine Office of the Attorney General could enforce violations as unfair trade practices. Anyone in violation could be subject to a civil penalty of no more than $5,000. A federal law is supposed to prevent automated bots from buying tickets, but concert promoters say it’s rarely enforced. Danna Hayes, a spokesperson for the attorney general’s office, said Friday that she did not have any comment yet on how the new law will be enforced.

Lauren Wayne, president of State Theatre Presents in Portland, said she won’t hesitate to turn to state officials instead.

“We’ll be reporting all the violations that we know about, which we can easily find through our ticketing site and because we’ve been doing this for so long,” Wayne said. “We have no qualms about having the attorney general’s information handy and readily available to hand out at shows.”