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2025 SENATE BILL 142
March 21, 2025 - Introduced by Senators ROYS, DASSLER-ALFHEIM, DRAKE,
HESSELBEIN, KEYESKI, LARSON, PFAFF, RATCLIFF and SPREITZER, cosponsored
by Representatives BROWN, ANDERSON, ANDRACA, ARNEY, BARE, CLANCY,
DESMIDT, FITZGERALD, HONG, J. JACOBSON, KIRSCH, MADISON, MCCARVILLE,
PALMERI, PHELPS, ROE, SINICKI, STROUD, SUBECK, TAYLOR and TENORIO.
Referred to Committee on Government Operations, Labor and Economic
Development.
***AUTHORS SUBJECT TO CHANGE***
AN ACT to create 704.44 (11) and 704.60 of the statutes; relating to:
algorithmic software for residential housing, and providing a penalty.
Analysis by the Legislative Reference Bureau
This bill prohibits the use of algorithmic software in setting rental rates or
occupancy levels for residential dwelling units and prohibits persons from selling,
licensing, or providing algorithmic software to a residential landlord. XAlgorithmic
softwareY is defined in the bill to mean software that uses an algorithm to perform
calculations on nonpublic competitor data regarding rent or occupancy levels in this
state for the purpose of informing a landlord[s decision regarding residential
housing occupancy rates, whether to leave a residential unit vacant, or the amount
of rent that a landlord may obtain for a residential unit. The Department of
Agriculture, Trade and Consumer Protection, the attorney general, or a district
attorney may investigate violations of this bill, and the attorney general or a district
attorney may commence an action seeking an injunction or to recover a civil
forfeiture of up to $1,000 per violation. In addition, a tenant may file a civil action
seeking actual damages incurred as a result of a violation of the bill or $1,000 per
violation, whichever is greater, or for injunctive relief, or for a combination of
injunctive relief and damages.
Under the bill, if a landlord includes a provision in a lease that 1) waives the
landlord[s obligation to comply with the prohibition on the use of algorithmic
software or 2) discourages or impedes a tenant from filing an action seeking
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injunctive relief or damages stemming from the landlord[s violation of the bill[s
prohibitions, then the rental agreement is void and unenforceable.
The people of the state of Wisconsin, represented in senate and assembly, do
enact as follows:
SECTION 1. 704.44 (11) of the statutes is created to read:
704.44 (11) Waives the landlord[s obligation to comply with s. 704.60 (2) or
discourages or impedes a tenant from filing an action or seeking injunctive relief or
damages under s. 704.60 (3).
SECTION 2. 704.60 of the statutes is created to read:
704.60 Use of algorithmic software. (1) DEFINITIONS. In this section:
(a) XAlgorithmic softwareY means software, including revenue management
software, that uses an algorithm to perform calculations on nonpublic competitor
data regarding rent or occupancy levels in this state for the purpose of informing a
landlord[s decision regarding residential housing occupancy rates, whether to leave
a residential unit vacant, or the amount of rent that a landlord may obtain for a
residential unit. XAlgorithmic softwareY includes a product or device that
incorporates algorithmic software. XAlgorithmic softwareY does not include any of
the following:
1. A publication of existing aggregated rental data if the publication does not
recommend rental rates or occupancy levels for future leases.
2. A product used for the purpose of establishing rent or income limits in
accordance with affordable housing guidelines or requirements of a local, state, or
federal program.
(b) XNonpublic competitor dataY means housing-related information that is
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not available to the general public regarding actual amounts charged for rent,
occupancy rates, lease start and end dates, or similar data, regardless of whether
the information is attributable to, derived from, or otherwise provided by a person
that competes in the same or related market.
(2) ALGORITHMIC SOFTWARE. (a) No person shall sell, license, or provide to a
residential landlord algorithmic software.
(b) No person may use algorithmic software to set rental rates or occupancy
levels for residential dwelling units.
(3) ENFORCEMENT AND PENALTY. (a) The department of agriculture, trade
and consumer protection, the attorney general, or a district attorney may
investigate an alleged violation of sub. (2).
(b) The attorney general or a district attorney may commence an action in the
name of the state to restrain by temporary or permanent injunction a violation of
sub. (2) or to recover a civil forfeiture of up to $1,000 per violation. The court shall
award the attorney general or district attorney court costs and, notwithstanding s.
814.04 (1), reasonable attorney fees, if the attorney general or district attorney is
the prevailing party in the action. Each month in which a violation exists or
continues constitutes a separate offense. Each dwelling unit for which a person has
used algorithmic software in violation of sub. (2) (b) constitutes a separate offense.
(c) A tenant may file a civil action for a violation of sub. (2) on behalf of himself
or herself, or on behalf of himself or herself and all persons similarly situated, for
actual damages incurred as a result of a violation of sub. (2), or damages of $1,000
per violation, whichever is greater, or for injunctive relief, or for a combination of
damages and injunctive relief. The court shall award the tenant court costs and,
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notwithstanding s. 814.04 (1), reasonable attorney fees if the tenant is the
prevailing party in the action. The court may also award any equitable relief to a
prevailing party as may be determined by the court if the tenant, or the tenant and
all persons similarly situated, is the prevailing party in the action.
(END)
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