Sens. Ted Cruz (R-TX) and Jacky Rosen (D-NV) introduced the Senate version of the Muhammad Ali American Boxing Revival Act on Thursday, and the bipartisan bill differs from the version the House passed in March in several areas, including contract lengths, title recognition, and federal compliance reviews, according to ESPN, which obtained an advance copy of the legislation.

“Fighters will have more options, fans will get more of the fights they want to see, and organizations will have to earn success by delivering for both,” Cruz said in a statement to ESPN. “The legislation also strengthens protections for boxers, modernizes safety standards, and creates a more competitive framework for the sport while helping preserve one of America’s most cherished traditions for future generations.”

The Senate bill keeps the House framework, which allows the creation of Unified Boxing Organizations, entities that could handle promotion, rankings, titles, and sanctioning under one structure as an option alongside the existing sanctioning body system. The differences are in the details.

Under the Senate version, a fighter’s first contract with a UBO would be capped at three years, provided the fighter has not previously signed a promotional agreement. Subsequent deals could run up to six years. Fighters could begin negotiating new deals 90 days before any contract expires, tripling the 30 day window in the House bill. The structure matches the contract terms BoxingInsider reported this week were circulating among sanctioning body stakeholders ahead of introduction.

Rosen told ESPN the longer negotiation window is meant to keep boxers from making rushed decisions. “Why is that important? If you sign on, let’s say you’re 17 or 18 and now you’re locked in and someone puts you in a 10-year contract, that’s maybe the life of your whole career as a boxer,” she said. “That really isn’t fair to the young person, the young athlete who is trying to get their foot in the door and make their way in their sport.”

On titles, the Senate bill would allow UBOs to recognize other organizations’ titles and rankings, whether another UBO or one of the four major sanctioning bodies, a provision absent from the House bill that opens the possibility of cross-organization matchups and undisputed champions. The Senate version also removes the House bill’s requirement of one championship per weight class for each sanctioning body or UBO.

The Senate bill adds disclosure and compliance reviews by the Federal Trade Commission and the Association of Boxing Commissions around the ratings process, including an avenue for fighters to appeal. It preserves the firewall between UBOs and boxing managers found in the current Ali Act, prohibits UBOs from charging fighters fees for title contests, and requires UBO fighters to have access to training and rehabilitation facilities at reasonable cost near where they live, rather than facilities operated by the UBO as in the House bill. Both versions guarantee at least $200 per round and at least one covered fight every six months. The Senate bill would take effect 180 days after enactment, up from 30 days in the House version.

Rosen told ESPN her team met with Nico Ali Walsh to discuss the Senate version. Ali Walsh, who testified against the House bill at the Senate Commerce Committee’s April 22 hearing, said Tuesday on The Ariel Helwani Show that senators had told him the legislation would not pass in its current form and identified financial transparency, free agency, contract length, and rankings transparency as the four changes he pushed in his meeting with TKO Group Holdings executives in New York last weekend. The contract and rankings provisions in the Senate bill address two of those four directly.

The House passed H.R. 4624 by voice vote on March 24. Two members who voted for it, Reps. Bobby Scott (D-VA) and Ilhan Omar (D-MN), publicly called on the Senate to strengthen protections against coercive contracts, forced arbitration, and monopoly provisions before passage.

TKO, which owns WWE, the UFC, and part of Zuffa Boxing alongside the Saudi Arabian entertainment company Sela, has backed the legislation, and Zuffa is widely expected to become a UBO if it passes. Per ESPN, both Dana White and Nick Khan issued statements Thursday supporting the Senate version.

The bill now sits with the Senate Commerce Committee, which Cruz chairs, with potential amendments expected after the August recess. If the committee and the full Senate approve it, the two chambers would need to reconcile their versions before the 119th Congress ends January 3, or the process restarts from scratch.