Most of the investors want to earn money. And where do they get it from? The spectators." Bayer Leverkusen and Wolfsburg are two special cases in the Bundesliga, based on the fact that investors who have had an interest in a club for more than 20 years can be granted an exemption from the 50+1 rule.

Leverkusen have won one Bundesliga, one DFB-Pokal, and one UEFA Cup. They also finished runners-up in the 2001–02 UEFA Champions League, losing 2–1 to Real Madrid in the final. They hold the European record for unbeaten competitive games, currently standing at 50. Their local rivals are 1.

It can be either habitational (derived from Bayer, which is the male German language demonym for Bavaria) or occupational (derived from the archaic German verb beiern, "to ring (a bell)", thus referring to individuals tasked with ringing church bells).

The club has won one UEFA Cup, one DFB-Pokal, and won their first Bundesliga title in the 2023–24 season. They have also finished runners-up five times in the Bundesliga and once in the UEFA Champions League.