The "Championship Belt" concept comes from boxing/wresting and is the idea that every season, the previous years champion (here the Super Bowl) starts with the belt, and each time they lose they pass the belt to the winning team who becomes the new sole owner.
The concept is explained here:
https://grantland.com/the-triangle/introducing-the-nba-regular-season-championship-belt/
The Seattle Seahawks finished the season with the 2024 championship belt by defeating the Rams in Week 18.
Week 0: Chiefs
Week 1: Chiefs defended against Ravens
Week 2: Chiefs defended against Bengals
Week 3: Chiefs defended against the Falcons
Week 4: Chiefs defended against the Chargers
Week 5: Chiefs defended against the Saints
Week 6: Chiefs defended against the Bye Week
Week 7: Chiefs defended against the 49ers
Week 8: Chiefs defended against Raiders
Week 9: Chiefs defended against Buccaneers
Week 10: Chiefs defended against Broncos
Week 11: Bills take belt from the Chiefs
Week 12: Belt takes a break for the Bills Bye Week
Week 13: Bills defended against 49ers
Week 14: Rams take belt from the Bills
Week 15: Rams successfully defend belt from 49ers
Week 16: Rams successfully defend the belt against the Jets
Week 17: Rams successfully defend the belt against the Cardinals
Week 18: Seahawks take belt from Rams
This market closes at the conclusion of the regular season, resolving simply with the team who holds the belt after Week 18. I'll update each week with the current owner of the belt. As a fun edge case, a tie would resolve in a division into two different belts (and could resolve for multiple teams).
Also See:
/StopPunting/who-will-hold-the-202324-last-year
/StopPunting/how-many-unique-bird-teams-will-own
/StopPunting/how-many-unique-cat-teams-will-own