What is the Bundesliga's 50+1 ownership rule?

The 50+1 ownership rule allows football fans to hold a controlling interest in German Bundesliga clubs. This means members are able to hold 50%, plus one more vote, of voting rights, which protects clubs from single investors under current antitrust laws. Most clubs in the Bundesliga are overseen by parent companies, while their teams are operated by commercial entities which have the primary goal of making a profit through football.