Buffalo, N.Y., firm Eric Mower and Associates issued a statement Tuesday saying Rob Hopkins is no longer employed there.
The Bills banned Hopkins from Ralph Wilson Stadium a day earlier. Erie County sheriff's officials say he could face charges.
Hopkins was seen on video sliding in a seated position down a 300-level railing during Sunday's Bills game against the New York Jets and then toppling backward and falling about 30 feet into the 200 section. Authorities say he landed on another fan.
Both men were taken to a hospital and later released.
Hopkins hasn't responded to a phone message left at his home Tuesday.