MD SB609

Landlords are prohibited from using algorithmic devices that incorporate nonpublic competitor data (such as actual rent prices, occupancy rates, and lease dates) to set or adjust residential rent amounts

"Algorithmic device" is defined as technology using algorithms to calculate rent recommendations based on local or statewide rent data from other landlords

Exemptions include monthly trade association reports with aggregated anonymous data and tools used to establish affordable housing program rent limits

Violations constitute an unfair, abusive, or deceptive trade practice under the Maryland Consumer Protection Act, subject to its enforcement and penalty provisions

The law applies prospectively only to rental agreements executed on or after the effective date of October 1, 2025