Senate Bill No. 400 amends existing laws regarding the handling of abandoned buildings by municipalities in Oklahoma. The bill defines an abandoned building as one that is unoccupied and has been declared unsecured or dilapidated. It establishes procedures for municipalities to abate public nuisances caused by such buildings, including providing at least ten days' notice to property owners and mortgage holders before a hearing is held. The bill also allows for the designation of an administrative officer to carry out the governing body's duties and provides property owners the right to appeal decisions made by this officer.

Additionally, the bill introduces a new section that allows municipalities to declare buildings unoccupied if they have remained so for over 365 days, causing increased municipal costs and devaluing nearby properties. Similar notice and hearing procedures are required before a building can be declared unoccupied and subject to abatement. The bill includes provisions for the assessment of costs related to the abatement process and establishes that these costs will create a lien against the property if not paid. The effective date for this legislation is set for November 1, 2025.