We know we're breaking the first rule of Fight Club here, but we need to talk about Fight Club. Mostly that they can't be hosted on city property, or as part of any unsanctioned sporting event.
Sec. 18-150. - Violent entertainment, unsanctioned sporting events.
(1)No person shall publicize, promote, conduct, sponsor, sanction or engage in any unsanctioned sporting event or a violent form of entertainment on City property.
(2)For the purposes of this section, an unsanctioned sporting event or a violent form of entertainment shall include, extreme fighting, ultimate fighting, full-contact fighting, "no-holds-barred" fighting, "tough man" contests, mixed martial arts or bare knuckle fighting.
(3)This section shall not prohibit state or nationally sanctioned boxing matches, or any other contest for which there is a commission or governing body that is recognized by the City as being an authentic and valid commission or governing body.
(4)Any person adjudged guilty of this provision shall be fined as follows:
First offense: $100 - $500
Second and subsequent offenses: $250 - $500
Original source can be found here.