Philly officials say a pro sports team paid big to boost Jeff Brown for mayor. The Sixers have ties to that super PAC.

In a lawsuit filed Monday alleging mayoral candidate Jeff Brown illegally coordinated with a political action committee backing his campaign, the Philadelphia Board of Ethics noted the group’s anonymous donors included a “professional sports team” that gave $250,000 to boost Brown.

The filing didn’t name the team, but sources told The Inquirer the donation was not made by the Phillies, Eagles, or Flyers. The Sixers did not respond to repeated requests for comment on whether the NBA franchise donated to the outside group, also known as a super PAC.

The donation was made last fall as team ownership was building political support for a proposed new arena in Center City — and the Sixers already have a connection with the group backing Brown, The Inquirer has learned.

David Maser, a lawyer who organized the For A Better Philadelphia political action committee and a related nonprofit with the same name, has also recently worked as a consultant for 76ers ownership in relation to the arena proposal, according to an email from Maser to stakeholders in the project that was not included in the lawsuit and was obtained by The Inquirer.

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Asked Monday at a mayoral forum if the Sixers gave to the super PAC, Brown said he didn’t know.

“Because we don’t coordinate with the [group], we have no idea what they got,” he said. “We don’t know about their lawyer or about any of that.”

Whether the next mayor will support the 76ers’ proposal to build a new arena at 10th and Market Streets will likely be pivotal in deciding if the high-profile and controversial project becomes a reality. The possibility that the team has been secretly donating to an effort to promote one of the candidates running in the Democratic primary for mayor would send shockwaves through the race.

The candidates have been asked repeatedly about the arena, which would border Chinatown and has been opposed by neighborhoods groups there that fear it will displace their community. While almost all of the candidates have avoided giving a firm yes-or-no answer on the proposal, Brown has been among the most supportive of the major contenders.

Brown said last month he has met with the parties, including the Sixers, stakeholders in Chinatown, and Comcast Spectacor, which owns the Wells Fargo Center where the Sixers currently play.

“If we can address the realistic challenges of this project, then this project should move forward,” Brown said. “You can’t ignore Chinatown’s issues. They have to be addressed. Not the emotional ones, because we all get emotional. I’m talking about the real, real issues, like parking, congestion, those kinds of things.”

For A Better Philadelphia, which has raised more than $3 million to boost Brown, is hiding the identities of the people funding its operations by passing almost all of its money through a nonprofit that shares the same name but, because of a loophole, is not required to disclose its donors.

» READ MORE: The Philadelphia Board of Ethics is accusing mayoral candidate Jeff Brown of illegally coordinating with a super PAC

Maser organized both the PAC and the nonprofit. He did not respond to a request for comment Monday.

Everyone else who could confirm or deny whether the 76ers are the team that donated to the super PAC is also keeping their lips sealed.

Dan Siegel, a consultant for the super PAC, has declined to identify who was funding the group’s efforts.

A spokesperson for Brown’s campaign declined to comment on whether Brown solicited contributions from the Sixers.

And the team and its development arm did not respond to requests asking them to confirm or deny that the 76ers donated to the group backing Brown.

Super PACs like For A Better Philadelphia are allowed to raise and spend unlimited amounts of money, including with donations that exceed the city’s campaign contribution limits, as long as they do not coordinate with the campaigns or candidates they support.

The board said the alleged coordination by Brown meant spending from the super PAC to influence the outcome of the May 16 Democratic primary election is effectively an in-kind contribution to Brown’s campaign. That would mean that the groups have repeatedly violated Philly’s campaign finance law by exceeding the city’s limits on the size of donations, which this year are $6,200 for individual donors and $25,200 for organizations.

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A lawyer for the groups denied the ethics board’s allegations in a hearing Monday, and Common Pleas Court Judge Joshua Roberts issued an order temporarily blocking it from making further expenditures related to the mayor’s race while setting an April 24 hearing to make a final decision on the matter.

According to the ethics board’s lawsuit, a sports team donated $250,000 in September to the nonprofit arm of For A Better Philadelphia. Another entity that is “controlled by one of the sports team’s collaborators” had already contributed $150,000 to the nonprofit in two separate transactions, in December 2021 and August 2022, the board said.

On Nov. 16, Brown officially declared his candidacy for mayor. According to emails attached to the lawsuit, two weeks later, Maser emailed James Cauley, Brown’s campaign manager.

Maser said he was writing “on behalf of the development team” at an organization that was redacted in the attached emails. He asked to set up a briefing “for Jeff and his campaign team,” saying he’d be happy to organize the meeting. Cauley responded less than two hours later, writing to send some scheduling options.

The two went on to schedule a meeting at Brown’s campaign headquarters in Center City. On Jan. 3, deputy campaign manager Olivia Scanlon followed up with Maser to confirm the meeting, which was set for the following day.

Brown’s campaign declined to confirm whether the meeting took place.

Nicole Gainer, a spokesperson for the team’s development arm 76 Devcorp, said the group has “requested and/or completed briefing meetings with nearly every Mayoral candidate on the proposed arena project as part of its ongoing community engagement process.”

Inquirer staff writer Bea Forman contributed to this article.