Senate Bill SF No 816 proposes changes to a current law in Minnesota, specifically amending the rules about how certain properties can be used over time. The main point of this bill is to prevent municipalities from using amortization policies to phase out or eliminate certain property uses if those uses were legal when they started. This means that most existing businesses or properties cannot be forced to close or change just because a new law or ordinance comes in that wouldn't allow them to start up today.

However, there are exceptions to this rule. The bill allows cities to continue using amortization for specific types of businesses, namely adult-only bookstores, adult-only theaters, and similar businesses focused on adult content, as well as nonconforming industrial uses in areas of environmental justice concern, but only in major (first class) cities. This would let these cities tackle specific issues locally while broadly protecting existing lawful businesses from being retroactively affected by new zoning changes.