Related works: California Private Listing Law After Washington SSB 6091 — Broker Conduct Rules for Listing Visibility, Showing Access and Buyer Representation. A California statute can add access and representation rules to Washington’s visibility rule. Why Compass Needs Private Listings, The Inventory-Routing Premium — Compass, the Anywhere Merger, and the Multi-State Enforcement Window. Every state enforcer already holds an antitrust statute and a consumer-protection act that apply after the Anywhere merger. How State Attorney General Coalitions Form, Grow, and Hold. Lead states absorb the cost of theory and evidence, and other offices join when joining costs little. Compass’s Interpretation of “Public Marketing” May Draw Antitrust Scrutiny from State Attorneys General. State attorneys general hold three statutory vehicles, and a data preservation demand is the lowest-cost first step.
I. Executive Summary
On September 30, 2026 Compass chief executive Robert Reffkin told a conference of listing-service executives that Compass will sue any Multiple Listing Service (MLS) that fines agents for publicly marketing listings kept out of the MLS. He gave every MLS until October 6 to change its rules. He described the two-year fight as one for “the freedom to put a listing on our website.”
Reffkin’s description marks a change in the practice. Compass now advertises its exclusive listings on its own website, which carries listings from all its brands at every marketing stage. Compass listings marketed as coming soon also appear on Redfin.
Public advertising answers the old complaint about hidden homes and leaves a harder question. A listing advertised on a public website is visible to everyone, yet a buyer may still be unable to tour it or bid on it through the broker the buyer chose. Real Estate News reports that buyers can skip a Compass agent only for listings in the coming-soon phase. Visibility and access are separate problems, and access is now the antitrust question.
The California Regional Multiple Listing Service (CRMLS) raised the access question on the day of the ultimatum. CRMLS refused Compass’s demand and published its formal response. The response alleges that buyers had to drop their own agents to tour Compass listings held outside the MLS.
Compass says homeowners should be able to market any listing publicly without their agent facing fines. Neither CRMLS’s allegation nor Compass’s answer has been tested in any forum.
A lawsuit is unlikely to test them soon. Compass has said its suits begin in mid-October, and MindCast’s simulation for the companion California paper places a filing by year-end at 77–90%. The same simulation places a court order on CRMLS’s rule by the end of 2027 at 14%. The one pending federal case on Compass’s listing practices was paused on September 15, when the court sent related claims against a Chicago-area MLS to private arbitration.
A state attorney general can test both accounts without waiting for a court. Existing antitrust, consumer-protection and licensing laws give the office authority to demand documents. Whether those laws also support a claim depends on the answers.
Access can be measured. Six questions turn the dispute into numbers an attorney general can request from listing histories, showing logs and offer logs. The first request is a demand that Compass preserve those files.
The same evidence reads the same in every state. A file built in one state lowers the cost for a second attorney general to act. Access is therefore the evidence that connects a private MLS dispute to state enforcement.
MLS leaders and state REALTOR associations hold the first evidence: accounts from buyers and agents, counts of listings advertised outside the MLS and the demand letters themselves. Both groups also carry a handicap, because an enforcer discounts a complaint brought by a competitor’s trade group.
The request that survives the discount is narrow. MLSs and associations should disclose their commercial interest, ask for a preservation demand and ask that the six questions be put to Compass. Neither group should ask an attorney general to approve an MLS rule or to file a brief in a Compass suit.
Each MLS should also decide its own rules by its own board vote. Petitioning a state official together is protected, and an agreement among MLSs on rule responses carries antitrust exposure.
MindCast’s companion California paper proposed a statute that writes access into law. The present paper covers what enforcers can do before any statute passes. An inquiry also produces the evidence a legislature needs.
MindCast analyzes the contest with Predictive Behavioral Economics + Dynamic Game Theory through the MindCast AI Proprietary Cognitive Digital Twin Foresight Simulation (MP CDT FS). Each institution becomes a Cognitive Digital Twin (CDT) with its own incentives and decision rules. Game theory supplies the payoff structure, and behavioral economics supplies the actors’ decision rules.
Two Chicago School ideas carry the economic argument. Coase explains why Compass and the MLSs cannot bargain to a result while each side defines the dispute differently. Stigler explains why enforcement should not depend on one federal office.
MindCast’s simulation for this paper tests how far the access mechanism carries. A pleading against Compass alleges denied access by June 30, 2027 at 48–64%. A second state attorney general takes a public step by the same date at 34–50%. No Republican-led attorney general acts in that window at 84–93%.
Access evidence lowers the cost of entry without making early entry likely. The first observable movement is more likely to appear in a pleading than in state coordination. A document signed by five or more attorneys general stands at 14–28%through 2027.
Each Simulation Prediction leaves an institution exposed if it waits. Showing logs and offer logs age out under ordinary retention, and motion practice can keep access allegations out of court for months. The first dated action in the paper is a preservation demand by March 31, 2027.
The Six Questions in Brief
Six questions turn access into numbers an attorney general can request.
Share: Compass’s portion of listings in the state’s largest markets.
Routing: the portion of those listings that begins as an office exclusive.
Information: whether the public display carries the fields Compass’s own network sees.
Access: whether a buyer with another brokerage can tour and offer on equal terms.
Representation: how often a Compass-affiliated agent represents the buyer.
Outcome: offers received and closing amounts against comparable MLS listings.
Simulation Prediction Highlights
The simulation for this paper released seven Simulation Predictions. Three are primary and four are secondary.
P-1 · 34–50%. A state attorney general other than New York’s takes a public step on Compass’s listing practices by June 30, 2027.
P-2 · 48–64%. A pleading against Compass alleges denied showings, denied offers or a forced change of representation by June 30, 2027.
P-3 · 84–93%. No Republican-led attorney general takes a public step through June 30, 2027.
Six previously published Simulation Predictions also apply. Section IX lists them apart from the new entries.
Stakeholder Readout
Four audiences carry an exposure the paper ties to a first action. No action removes an exposure entirely.
🏛️ Attorneys General and Regulators: listing histories, showing logs and offer logs age out before any inquiry opens. First action: a preservation demand to Compass by March 31, 2027.
🗂️ MLS Leaders: no state enforcer is expected to act in Republican-led states through mid-2027, so an MLS there relies on its own rules and defense budget. First action: a litigation reserve in the 2027 budget.
🤝 REALTOR Associations: a state office can receive the file and stay silent through mid-2027. First action: deliver the six-question file with consumer statements to one office by March 31, 2027.
⚖️ Counsel: access allegations stay out of court for months if an MLS moves to dismiss before answering. First action: collect signed buyer and agent statements before the first response deadline.
II. The Access Question and the Evidence Compass Supplies
A dispute over MLS fines has become a question about who may show and sell an advertised home. Compass’s own statements supply the first evidence on that question.
A. Current State: The Demand, the Refusal and the Untested Allegations
The dispute first reached court in Washington. Compass sued the Northwest Multiple Listing Service (NWMLS) in April 2025 over rules that barred marketing a home before it entered the MLS. The parties ended that case with an August 31 agreement under which every listing still enters the MLS.
MindCast’s The Compass–NWMLS Settlement Changed the Private Governor After Washington Changed the Governing Law explains the agreement. The paper matters here because it shows that Washington’s statute carries the binding rule and the MLS agreement sits above it.
Compass wrote to CRMLS eight days later. The September 8 letter demanded that CRMLS stop fining agents who publicly market office exclusives, which are listings a brokerage keeps out of the MLS. The letter set an October 6 deadline and threatened a federal antitrust suit. Inman reports that the letter commits Compass to spend millions of dollars suing CRMLS and other MLSs.
Compass copied the letter to the Justice Department’s Antitrust Division and the Federal Trade Commission’s Bureau of Competition. The letter names eight MLSs that permit public marketing of office exclusives. Reffkin has offered any MLS that agrees by October 6 a release of Compass’s claims and a data feed of its office exclusives.
CRMLS refused on September 30. General Counsel Ed Zorn wrote that Rule 7.9 already lets a seller market a home publicly without MLS submission under an open or non-exclusive listing. The rule requires submission only when a broker holds an exclusive listing agreement. CRMLS says the limit prevents free riding by a broker who uses competitors’ MLS data to win a listing.
CRMLS’s response also alleges conduct by Compass agents. CRMLS says buyers had to abandon their chosen agents to tour Compass listings held outside the MLS. CRMLS says one Compass agent required a buyer to list the buyer’s own home with that agent before granting access. MindCast treats both statements as allegations by one party to the dispute.
CRMLS widened the contest beyond two parties. Zorn listed seven counterclaims CRMLS would bring if Compass sues, including a group boycott claim under the Cartwright Act, California’s antitrust statute. CRMLS announced an MLS Cooperation Legal Defense Fund and requested money from the legal funds of the California Association of REALTORS (C.A.R.) and the National Association of REALTORS (NAR).
Compass answered the same day. A spokesperson told RISMedia that Compass would take the CRMLS dispute to the courts. Reffkin told the conference that Compass will not end its suits by agreement.
B. Visibility and Access Are Separate Problems
A home listing carries two separate properties. Visibility determines which buyers learn the home is for sale. Access determines which brokers may show the home and present an offer.
MLS submission bundles the two. A listing entered in the MLS reaches public websites and carries an offer of cooperation to every member broker. A publicly advertised office exclusive delivers the first property and withholds the second.
Washington’s statute shows the gap. The Washington Department of Licensing states that marketing to the general public does not require an owner to allow access onto or into the property. The statute is silent on whether a listing broker may favor its own buyers in showings and offers.
Visibility is only the first step in a purchase. A buyer who sees a home must still obtain full information, tour it and submit an offer. Each step can be made easier for the listing brokerage’s own buyers than for anyone else’s.
MindCast’s From Inventory Control to Attention Control: The Compass Commission-Consolidation Model After First Look examined the steps after visibility in Washington. The paper matters here because its lead Simulation Prediction, published at 62–68%, places the listing brokerage’s remaining advantage with buyers who arrive without an agent.
C. Why Predictive Behavioral Economics Adds Value
Behavioral economics describes the decision rules people use in place of an even weighing of costs and benefits. Three of those rules shape the route to an attorney general.
The first rule concerns attention. Hidden listings were the salient harm, so legislators and consumer groups anchored on secrecy. A reform anchored on visibility is satisfied the moment a listing appears on a public website.
The second rule concerns buyers, who follow defaults. A buyer without an agent contacts the name beside the listing. Whoever controls that first contact gains the first chance to represent the buyer.
The third rule concerns enforcers, who discount a message by its source. A complaint from a competitor’s trade group receives less weight than the same facts from a consumer. The form of the request therefore matters as much as its content.
D. Why Dynamic Game Theory Adds Value
Game theory supplies the payoff structure for each institution’s choice. A brokerage that sells a home to a buyer represented by its own agent keeps both sides of the commission. Cooperation shares the buyer side with a rival. The gain from withholding cooperation grows with the brokerage’s share of local listings.
Cooperation among brokers is an equilibrium that holds only while each member expects the others to share. A member large enough to gain from withholding changes the calculation for everyone else. Rivals must follow or lose buyers.
Compass’s litigation threat gains leverage when each MLS weighs the cost of resistance alone. An MLS that receives a demand letter compares the cost of a federal defense with the cost of a rule change. CRMLS’s defense fund changes that comparison by pooling the cost.
A rule change obtained under threat of suit is not evidence that a market prefers the rule. MindCast’s The Dual Nash-Stigler Equilibrium Architecture describes outcomes that look stable and rest on coercion, missing information or absent enforcement. An attorney general should read any MLS concession after October 6 in that light.
Private bargaining stalls while the two sides define the dispute differently. MindCast’s The Chicago School Accelerated Part I, Coase and Why Transaction Costs ≠ Coordination Costs separates the cost of making a deal from the cost of agreeing on what the deal concerns. The paper matters here because Compass bargains over advertising and the MLSs bargain over cooperation. Parties who disagree about the object of a negotiation have no bargaining range.
An attorney general’s inquiry changes the game in a different way. Compass decides whether a lawsuit is filed and when it ends. Compass does not decide whether a state office asks for documents.
E. Compass’s Own Statements Supply the Starting Evidence
Compass has described its listing strategy four ways since 2024. Each description carries an implication for an access inquiry.
Exclusive inventory, told to investors.
In February 2025 Compass told shareholders that its pre-marketed listings were “only available by working with a Compass agent or by searching Compass.com.”
The 2025 proxy statement said acquisitions would enhance its “inventory advantage.”
Access implication: exclusivity is presented as the source of advantage.
Seller choice, told to the public.
Reffkin told analysts in 2025 that 94 percent of listings eventually reach the MLS.
Access implication: the private phase is a delay, and the value of a delay depends on who can act during it.
Victim of gatekeepers, argued as plaintiff.
Compass sued NWMLS and Zillow in 2025 over control of how listings are marketed and distributed.
In April 2026 Compass partnered with Midwest Real Estate Data (MRED), the Chicago-area MLS, and Zillow sued both in May.
Access implication: control over listing distribution can restrain competition.
Freedom to advertise, told to MLS executives.
Compass’s “See It First” site carries listings from all its brands at every marketing stage.
Real Estate News reported that buyers can skip a Compass agent only for listings in the coming-soon phase.
Access implication: the home is advertised to the public and withheld from MLS cooperation.
MindCast’s Compass’s Cross-Forum Contradictions collects the investor statements. An access inquiry would cite the same documents.
🏛️ Attorneys General and Regulators: the opening file for an inquiry already exists in Compass’s securities filings, press releases and public remarks.
III. A Lawsuit Is Likely and a Court Answer Is Not
Compass’s suits will probably arrive, and they will probably not decide the access question soon. MindCast’s California simulation places a Compass complaint against at least one MLS by December 31 at 77–90%. The same simulation places a court order that changes enforcement of CRMLS’s rule by the end of 2027 at 14%.
Two private suits show why. Compass sued Zillow in June 2025, a federal judge in New York denied its injunction request in February 2026 and Compass dismissed the case. Zillow then sued MRED and Compass in Chicago.
MindCast’s The Compass–Zillow Antitrust Litigation Arc Is Closed. Here Is What the Record Shows. reviews the New York case. For a state enforcer the point is that the suit ended without a decision on the merits.
On September 15 Judge John Tharp denied Zillow’s request for a preliminary injunction. The court found Zillow had not shown an unlawful agreement or substantial harm to competition at that stage. Zillow’s claims against MRED went to private arbitration, and its claims against Compass are paused.
Compass announced that the ruling strengthens the path to nationwide adoption of its marketing program. The ruling is the strongest authority Compass holds. The one public proceeding in which Compass’s partnership documents faced discovery has stopped.
Pleadings may also arrive late. NWMLS moved to dismiss before answering Compass’s Washington suit and asserted its counterclaims about a year after the complaint. A defendant MLS that follows the same sequence delays any access allegation.
MindCast’s simulation for this paper places at least one Compass suit against an MLS ending before a merits ruling at 43–59%, given a filing. Private litigation can end by dismissal, rule change or arbitration. A state inquiry does not depend on Compass’s decision to keep litigating.
State and federal officials hold a route Compass cannot close. New York’s attorney general opened an antitrust inquiry in June and contacted leaders of rival brokerages. The House Judiciary antitrust subcommittee requested briefings from Compass and MRED in July.
🗂️ MLS Leaders: a board that waits for a court to gather the facts may wait past 2027.
IV. The State Laws That Give an Attorney General Authority to Ask
No state statute reviewed by MindCast contains a rule written for showing and offer access. General antitrust, consumer-protection and licensing laws fill part of the gap. The same laws give an attorney general authority to investigate, and the facts decide whether a claim follows.
A. Antitrust Statutes
State antitrust laws reach agreements that restrain trade. A partnership between a national brokerage and an MLS is an agreement an attorney general can examine. CRMLS’s listed counterclaims include a claim under California’s Cartwright Act.
MindCast’s How the Zillow Complaint Reframes Compass v. NWMLS as a National Coordination Case analyzes the agreement theory. A state reviewer can adapt the group-boycott claim the paper explains.
An attorney general can also bring federal antitrust claims for state residents under section 4C of the Clayton Act. MindCast’s Compass’s Interpretation of “Public Marketing” May Draw Antitrust Scrutiny from State Attorneys Generallists the statutes that carry a state claim. The paper matters here because it found that California’s Cartwright Act and New York’s Donnelly Act reached agreements and not single-firm conduct.
California closes that gap for public enforcers on January 1, 2027. Assembly Bill (AB) 1776 extends the Cartwright Act to monopolization, and only the Attorney General and district attorneys may enforce it. The new authority applies only where a firm holds substantial market power.
MindCast’s Federal Inaction Has Elevated State Authority on Consumer Protection, Antitrust, and Market Integrityaddressed market share in January. The briefing matters here because it estimated Compass’s combined share above 30 percent in Manhattan, San Francisco and Chicago.
B. Consumer-Protection Acts
Consumer-protection acts reach unfair and deceptive practices. A home advertised to the public on terms that limit who may show it raises a question those acts cover. California’s Unfair Competition Law (UCL) gives public prosecutors a civil remedy. Washington’s Consumer Protection Act holds both the deceptive-practices provision and the state antitrust provisions.
MindCast’s State Power vs. Compass Private Exclusives sets out the consumer-protection route. The paper argues that inconsistent statements to different audiences can be deceptive conduct under those acts.
C. Licensing Laws
Licensing regulators discipline brokers directly. The California Department of Real Estate (DRE) holds that authority in California, and Washington’s Department of Licensing enforces that state’s listing law. California already requires a written buyer-broker agreement under Civil Code section 1670.50.
D. Listing Statutes
Wisconsin, Washington and Connecticut have listing statutes in force, and New York’s Legislature passed its act in June. Connecticut’s law took effect on October 1. A seller who keeps a listing off public channels must sign an opt-out, and each signed form documents a withheld listing.
A listing statute can be avoided. MindCast’s Compass Plan B, Structural Circumvention After Washington SSB 6091maps the routes around Washington’s law. An enforcer in a statute state should check self-attested safety claims and buyer matching before a listing exists.
E. Federal Review Left the Question Open
Federal clearance of the Anywhere merger does not bind a state. Bloomberg reported that Justice Department officials allowed the deal after staff recommended further scrutiny. The report noted that state attorneys general could still act.
Enforcement that runs through one office is easier to close than enforcement shared among many. MindCast’s The Stigler Equilibrium- Regulatory Capture and the Structure of Free Markets develops the point from George Stigler’s work on regulation. The paper matters here because it explains why state offices with independent authority keep a market question open after a federal review ends.
MindCast’s January briefing named the same state tools used above: consumer-protection acts, state antitrust laws and licensing law.
F. An Inquiry and a Statute Work Together
General laws require proof that a conduct statute would not. A monopolization claim needs market power, and a deception claim needs a misleading practice. MindCast’s California paper proposes a statute that bars brokerage-based access limits without either showing.
An inquiry supplies what a statute needs first. The California paper names one evidence gap: CRMLS’s allegations come from one party and remain untested. A document request from an attorney general is the forum that tests them.
🏛️ Attorneys General and Regulators: no new statute is needed to ask the questions, and the answers show whether a new statute is needed.
V. Six Questions an Attorney General Can Answer From Documents
A state inquiry does not need to prove a national conspiracy. Six questions define the matter, and brokerage documents answer each one.
Share. What share of listings in the state’s largest markets belongs to Compass and its affiliated brands? Listing counts by brokerage answer the question, and the answer decides whether single-firm law applies.
Routing. What share of those listings begins as an office exclusive, and for how many days? Listing histories answer the question.
Information. Does the public display of an office exclusive carry the same fields the brokerage’s own network sees? Days on market and price-change history are the fields to compare.
Access. During the exclusive phase, can a buyer represented by another brokerage tour the home and submit an offer on equal terms? Showing logs and offer logs answer the question.
Representation. How often does a Compass-affiliated agent represent the buyer on a sale that began as an office exclusive? The comparison is the same rate on listings entered in the MLS from the first day.
Outcome. Do sales that begin as office exclusives draw fewer offers or close at different amounts than comparable MLS listings? Closed-sale data answers the question.
Questions three through five match the three protections in MindCast’s California paper: public information, showing and offer access and representation independence. The proposed California statute would require large brokerages to report pre-market duration and same-brokerage closings each year. The questions ask for the same data now.
MindCast’s Why Compass Needs Private Listings, The Inventory-Routing Premium — Compass, the Anywhere Merger, and the Multi-State Enforcement Window posed the questions on control, routing and harm in June. The paper matters here because it showed that a state inquiry can proceed on those questions without proof of a national conspiracy.
Information parity came from MindCast’s second June paper. Compass’s exclusive listings on Redfin omit days on market and price-change history under a February agreement. Access and representation are the additions, because Compass did not advertise office exclusives to the public at scale in June.
The fifth question should count buyers who arrived without an agent. A listing agent can represent those buyers as well.
An outside measurement of the fifth question already exists. MindCast’s Compass Double-Sided Commissions — Consumer Policy Center Measures the Output, MindCast Models the System discusses it. The paper sets a consumer group’s report on both-sides commissions beside MindCast’s Seattle transaction data.
A. The Outcome Question Needs More Than One State
Compass says pre-marketing helps sellers, and the sixth question tests the claim against all comparable sales. The cleanest test compares states. Washington bans the private phase, Wisconsin and Connecticut require a signed opt-out and California has no listing statute.
Sale outcomes across the three kinds of state isolate the effect of the exclusive phase. MindCast’s June analysis described the comparison as an experiment the legislatures built without intending to.
Compass has claimed a 2.9 percent premium for pre-marketed listings. MindCast’s Compass’s Coasean Coordination Problem Part III- Coordination Costs, MLS Governance and the Compass Litigation examines the claim and treats the premium as a cost to buyers.
B. The First Request Is Preservation
The lowest-cost first step is a demand that Compass preserve listing histories, showing logs and offer logs. A preservation demand requires no legal theory and commits no office to a filing. MindCast recommended the same first step for a coalition of states in June.
⚖️ Counsel: each question produces a number, and none requires a finding about intent.
VI. What MLS Leaders and REALTOR Associations Should Bring
An attorney general’s office will weigh who is asking. MLSs and REALTOR associations compete with Compass or represent its competitors. The briefing they bring must survive the discount an enforcer applies to an interested party.
A. Evidence to Bring
Buyer and agent accounts. Signed statements from buyers and agents who asked to tour an exclusive listing and were refused or redirected. CRMLS is collecting such accounts now.
Listing counts. The number of homes each brokerage advertised publicly without MLS submission, by month and market.
The demand and the answer. Any letter received from Compass and the MLS’s reply.
The rule and its reason. The text of each challenged rule with the competitive reason the board adopted it.
Compass’s own statements. The filings and remarks collected in Section II.
A board can test Compass’s argument before it writes to an enforcer. MindCast’s The Skillman Moment as Analytical Rosetta Stone of the MindCast MLS Equilibrium Series supplies three questions for that test. The answers show whether an argument holds outside the forum where it was first made.
B. Requests to Avoid
An endorsement of any MLS rule. The six questions can be answered without deciding whether a rule is lawful.
A penalty against a named competitor before the facts are gathered.
Any statement that MLSs have agreed among themselves how to answer Compass.
A brief in a Compass suit. A brief would place the state behind an MLS rule, and MindCast’s simulation finds states unlikely to take that position.
C. Legal Constraint on the Organizations Bringing the Briefing
A joint refusal agreed among MLSs carries its own antitrust exposure. The constrained version is an independent decision by each board, with pooled money limited to litigation defense.
Petitioning a state official together is protected. The Supreme Court held in Eastern Railroad Presidents Conference v. Noerr Motor Freight (1961) that competitors may jointly ask government to pass or enforce laws. A state REALTOR association can therefore carry evidence from several MLSs to one attorney general.
The organizations should state their commercial interest in the first paragraph of any letter. An enforcer who learns of the interest later discounts the rest of the file.
🤝 REALTOR Associations: bring consumer evidence and a request for an inquiry, and leave rule defense for the courtroom.
VII. Five Objections an Attorney General Will Raise
An attorney general’s staff will test the briefing before acting on it. Five objections are predictable, and each has a direct answer.
A federal judge just ruled for Compass. The Illinois ruling addressed a listing portal’s request for emergency relief. Buyer access to exclusive listings under state law was not the question before the court. A state inquiry also begins with document authority a private plaintiff lacks.
MLS boards are competitors writing rules for competitors. Reffkin makes the same point. The answer is the form of the request. The six questions concern Compass’s listings and Compass’s buyers, and none asks the attorney general to approve an MLS rule.
An MLS is also shared infrastructure. MindCast’s Compass’s Coasean Coordination Problem Part I, How Private Exclusives Reshape Competition and Threaten MLS Stability makes that case. The paper matters here because it identifies the MLS as the shared reference point that keeps the market complete for every buyer.
Sellers choose the program. A seller may decline the MLS, and California’s Civil Code section 1088 protects that choice. The access question begins once a broker advertises the home to the public. Buyers and their agents made no such choice.
MindCast’s Compass’s ‘Consumer Choice’ Rhetorical Framing as a Control Mechanism examines the seller-choice argument. The paper distinguishes two meanings of consumer choice and shows that a buyer’s choice depends on a complete market.
The listing is public, so no one is harmed. Visibility and access are separate. A buyer who must change agents to tour an advertised home bears a cost the advertisement does not disclose.
Private lawsuits will sort the matter out. Two private suits have already ended or paused without a public finding. Compass dismissed its case against Zillow, and Zillow’s case against Compass waits on a private arbitration. Private bargaining stalls for the reason given in Section II: the two sides disagree about what is being bargained over.
🏛️ Attorneys General and Regulators: each objection is answered by an inquiry into access and not by a ruling on MLS rules.
VIII. How State Inquiries Spread From One Office to Many
State enforcement against a national firm spreads by a known mechanism. Lead states absorb the fixed costs of building a legal theory and gathering evidence. Other offices join when joining costs little and the theory fits their own law.
Lower cost does not mean early entry. MindCast’s simulation places a second-state public step below even odds through June 30, 2027.
A. Access Evidence Travels Between States
Access evidence lowers the joining cost because it does not vary by state. Compass’s investor filings, its national website and its national ultimatum read the same in Albany and Sacramento. Visibility evidence varies with each statute. Washington bans the private phase, Wisconsin and Connecticut allow a signed opt-out and California has no listing statute.
Each kind of state also holds one part of the evidence. Washington holds conduct under a ban, the opt-out states hold signed forms and the states with no statute hold the baseline. No single office can assemble the full comparison alone.
B. Cross-Party Concern Exists and Attorney General Entry Has Not Followed
Concern about private listings crosses party lines. Representative Scott Fitzgerald of Wisconsin, a Republican, chairs the House subcommittee examining the MRED partnership. Washington’s listing statute passed 49–0 and 92–1, and New York’s Senate passed its listing act 60–0.
Consumer groups have asked for coordination. Nineteen of them wrote to state attorneys general in September about Zillow and Compass. The letter asked the attorneys general to form a multistate working group and share evidence.
The economic case for an inquiry rests on Chicago School authors. Coase explains why private bargaining stalls here, and Stigler explains why enforcement should not depend on one office. An office skeptical of regulation can accept both arguments.
No public step by a Republican-led attorney general on Compass’s listing practices has surfaced. The simulation finds no local suit, statute dispute or plaintiff in those states that would prompt a step before mid-2027. A Compass suit against an MLS in a Republican-led state, joined by consumer accounts, would change the reading.
C. Two Limits on a Large Coalition
Remedies differ by state, because a state with a ban and a state with no statute want different orders from a court. State variation therefore helps prove harm and complicates a common remedy. Framing also matters. An inquiry framed around the federal merger clearance sorts states by party, and an inquiry framed around listing access can draw both.
🤝 REALTOR Associations: begin with one office that has local evidence. A file built on the six questions can then travel to the next office unchanged.
IX. MindCast Simulation Predictions
The simulation for this paper released seven Simulation Predictions. Three are primary and four are secondary. P marks a Primary Simulation Prediction and S marks a Secondary Simulation Prediction.
A. Primary Simulation Predictions
Three primary Simulation Predictions state what happens in state enforcement and in the courts. P-2 is the first observable, because a pleading can arrive before any attorney general acts.
P-1 · A Second State Attorney General Takes a Public Step
Simulation Prediction: a state attorney general other than New York’s takes a public step concerning Compass’s listing practices.
Qualifying steps: an announced inquiry; a suit; a brief; a public letter; compulsory process reported by two named trade outlets.
Band: 34–50%
Window: October 3, 2026 through June 30, 2027.
Triggers: Compass sues a California MLS, consumer accounts reach a state office or New York invites other offices.
Falsifier: no office other than New York takes a qualifying step inside the window.
Verification source: attorney general releases and filings; reporting by Inman; HousingWire; Real Estate News; RISMedia; The Real Deal.
P-2 · A Pleading Against Compass Alleges Denied Access
Simulation Prediction: a complaint or counterclaim filed against Compass alleges that buyers or their agents were denied showings or offers on a listing kept out of the MLS, or were required to change representation.
Band: 48–64%
Window: October 6, 2026 through June 30, 2027.
Triggers: Compass files against an MLS and the defendant answers with counterclaims, or class counsel files a buyer suit.
Falsifier: no such pleading appears on any docket inside the window.
Verification source: the federal courts’ docket system (PACER) and state court dockets.
P-3 · No Republican-Led Attorney General Takes a Public Step
Simulation Prediction: no Republican-led state attorney general takes a qualifying step under P-1 or signs a multistate document concerning Compass’s listing practices.
Band: 84–93%
Window: October 3, 2026 through June 30, 2027.
Triggers: no local suit, statute dispute or plaintiff arises in a Republican-led state.
Falsifier: a Republican-led state attorney general takes any such step inside the window.
Verification source: attorney general releases and filings, with the same trade reporting as P-1.
P-3 concerns the window and not the long-run position of any office.
B. Secondary Simulation Predictions
Four secondary Simulation Predictions attach to New York, to multistate documents and to Compass’s suits. Two depend on a Compass filing and are void without one. California P-2 places that filing at 77–90%.
S-1 · 84–93%, given a Compass suit against an MLS. No state attorney general files a brief or statement of interest in a Compass suit against an MLS through December 31, 2027.
Trigger: the suits stay at the motion stage in trial courts.
Falsifier: any such filing on the docket of a Compass suit against an MLS.
S-2 · 22–38%. New York’s attorney general files suit, announces a resolution or publicly confirms compulsory process concerning Compass by December 31, 2027.
Trigger: evidence of in-house sale rates or denied access in New York.
Falsifier: no such New York action inside the window.
S-3 · 14–28%. Five or more state attorneys general sign one letter, comment or brief on private listings or Compass by December 31, 2027.
Trigger: a federal comment period on broker cooperation, or a letter drafted by a lead state.
Falsifier: no such document with five or more signatories inside the window.
S-4 · 43–59%, given a Compass suit against an MLS. At least one Compass suit against an MLS ends by voluntary dismissal or negotiated resolution before a merits ruling by December 31, 2027.
Trigger: a sued MLS changes its rule, or a court denies early relief.
Falsifier: every Compass suit against an MLS stays pending or reaches a merits ruling inside the window.
S-1 changes the advice in Section VI. A Compass suit does not give states a vehicle they will use, and an inquiry remains the route.
C. Previously Published Simulation Predictions
Six entries from two earlier MindCast papers bear on the same contest. Each keeps its published band.
California P-2 · 77–90%. Compass files an antitrust complaint against at least one MLS between October 6 and December 31, 2026.
California S-1 · 64–80%. A named institution publicly commits money to the MLS Cooperation Legal Defense Fund by March 31, 2027.
California S-3 · 58–74%. Compass files a complaint naming CRMLS between October 6 and December 31, 2026.
California S-4 · 82–92%. CRMLS keeps its submission rule through June 30, 2027.
Coalition P-1 · 66–78%. A national consumer-protection or platform matter reaches 25 to 40 jurisdictions only when a cross-party entrant joins before a complaint is filed.
Coalition P-3 · 80–90%. Every coalition above 25 members runs on an operating core of eight or fewer offices.
P-3 and Coalition P-1 explain S-3. Without a cross-party entrant, a document signed by five or more attorneys general remains unlikely through 2027.
D. Questions That Carry No Simulation Prediction Yet
Three questions carry no band yet, because each waits on an earlier fact. Which state acts second waits on a first public signal from any office. California’s use of its single-firm authority waits on the law’s effective date. The entry of Compass’s investor statements into a filing waits on a search of existing dockets.
MindCast will release a Simulation Prediction on each question once the earlier fact is known and before the event in question.
E. Limits of the Simulation Predictions
Two limits apply to the entries. The scope of New York’s inquiry is not public, and the simulation treats Republican-led offices as one group. Five events sit outside the contest the entries address.
A negotiated agreement between Compass and CRMLS before any filing.
Federal guidance or action on broker cooperation.
A merits ruling on an MLS submission rule.
A change of control at Compass.
An enacted state access statute.
Any of the five replaces the contest the Simulation Predictions address. MindCast validates every Simulation Prediction publicly against its named source.
Working With MindCast
MindCast AI is a Predictive Behavioral Economics + Dynamic Game Theory firm. The firm models how institutions decide and how each responds to the others, using CDTs built from public evidence.
A commissioned simulation models one institution from its own documents and tests the specific decision that institution faces. Four decisions raised in the paper are ready for that work.
🗂️ MLS Leaders: which evidence to bring and which rule questions to keep out of the request. The simulation tests each choice against the enforcer’s likely objections and Compass’s response.
🤝 REALTOR Associations: which office to approach first and whether to act alone or with other state associations. The simulation tests each sequence against the offices likely to join.
🏛️ Attorneys General and Regulators: whether an access theory fits the state’s statutes and which offices would join an inquiry.
⚖️ Counsel: how a state inquiry changes cost and timing in a Compass suit against an MLS.
Commissioned work also covers the three questions the paper leaves without a Simulation Prediction.
Clients receive complete probability distributions, complete scenario trees, decision thresholds tied to named triggers and a monitoring system.
A commissioned engagement begins with a scoped diagnostic session on one decision. Contact mcai@mindcast-ai.com to schedule one.
X. Exposure and Mitigation by Simulation Prediction
Each primary Simulation Prediction leaves an audience exposed if it resolves as stated and nothing was done. Each action below is one an institution takes alone. The actions are analytic options and not legal, investment or fiduciary advice.
P-2 at 48–64% · A Pleading Against Compass Alleges Denied Access
⚖️ Counsel: MLS general counsel
Exposure. Access allegations stay out of court for months if the MLS moves to dismiss before answering.
Mitigating actions.
General counsel collects signed buyer and agent statements before the first response deadline in any Compass suit.
General counsel decides before that deadline whether to answer with counterclaims or move to dismiss.
General counsel issues a litigation hold on showing and offer complaints before any Compass complaint is filed.
Residual exposure. The court sets the schedule, and Compass can move to dismiss any counterclaim.
P-1 at 34–50% · A Second State Attorney General Takes a Public Step
🤝 REALTOR Associations: chief executives and government-affairs directors
Exposure. A state office receives the file and takes no public step through mid-2027. The association cannot show members a result in that period.
Mitigating actions.
The government-affairs director delivers the six-question file with consumer statements to one state office by March 31, 2027.
General counsel drafts the disclosure of the association’s commercial interest before the file is sent.
The chief executive requests a preservation demand as the first step in the cover letter.
Residual exposure. The office decides alone and may remain silent.
🏛️ Attorneys General and Regulators: antitrust and consumer-protection chiefs
Exposure. Listing histories, showing logs and offer logs age out under ordinary retention before any inquiry opens.
Mitigating actions.
The antitrust bureau chief sends a preservation demand to Compass and its affiliated brands by March 31, 2027.
The consumer-protection chief requests the signed opt-out forms in states that require them by the same date.
Residual exposure. Data outside the demand is not preserved.
P-3 at 84–93% · No Republican-Led Attorney General Takes a Public Step
🗂️ MLS Leaders: chief executives in Republican-led states
Exposure. No state enforcer acts through June 30, 2027. The MLS relies on its own rules and its own defense budget in that period.
Mitigating actions.
The chief financial officer adds a litigation reserve line to the 2027 budget before the board’s next budget meeting.
General counsel prepares the six-question file for the state licensing regulator by March 31, 2027.
The chief executive puts any Compass demand to a board vote entered in the minutes.
Residual exposure. The licensing regulator may also decline to act, and defense costs can exceed the reserve.
The four entries share one feature. Every action is taken by one institution alone, and none depends on what Compass or a court does next.
XI. Signals to Watch
Nine public signals move the Simulation Predictions. Each has a named source and a stated consequence.
Complaint by Compass against any MLS (California P-2)
Source: federal and state court dockets.
Changes: confirms California P-2 and opens the windows for S-1 and S-4.
Pleading against Compass that alleges denied showings, denied offers or forced change of representation (P-2)
Source: the same dockets.
Changes: confirms P-2 and moves the access allegations into a forum that can test them.
Public step by a state attorney general other than New York’s (P-1)
Source: attorney general releases and trade reporting.
Changes: confirms P-1.
Public step by a Republican-led attorney general (P-3)
Source: attorney general releases.
Changes: falsifies P-3 and supplies the cross-party entrant under Coalition P-1.
State brief in a Compass suit against an MLS (S-1)
Source: the dockets of those suits.
Changes: falsifies S-1.
New York suit, resolution or confirmed compulsory process (S-2)
Source: New York attorney general releases.
Changes: confirms S-2.
Document signed by five or more attorneys general (S-3)
Source: attorney general releases and the National Association of Attorneys General.
Changes: confirms S-3.
Dismissal or negotiated resolution of a Compass suit against an MLS (S-4)
Source: the dockets of those suits and MLS rule notices.
Changes: confirms S-4.
Court holding or federal guidance that public advertising answers the competition question
Source: court orders, and the Justice Department and Federal Trade Commission, which are reexaminingtheir guidelines. Reffkin has cited a 1971 NAR policy for that position.
Changes: replaces the contest the Simulation Predictions address.
MindCast publishes an update when a signal confirms or falsifies an entry.
XII. Conclusion
Compass’s ultimatum put a question before every MLS board, and the question is larger than any board’s rulebook. A home can be visible to every buyer and open only to one brokerage’s buyers. Whether that happens in practice is a matter of fact.
Courts are unlikely to establish the facts soon. A suit is probable and a court order is not, and the one pending case is paused behind a private arbitration. State attorneys general can establish the facts with a preservation demand and six document requests.
The Simulation Predictions set the expectation. A pleading is the most likely first sign of movement. A second-state public step stays below even odds through June 2027, and no Republican-led office is expected to act in that period.
The decisive signal is the first pleading filed against Compass after October 6. The pleading’s allegations resolve P-2 and show whether the access question has reached a forum that can test it.
MLS leaders and REALTOR associations hold the first evidence. Their request carries weight when it asks for an inquiry, discloses their interest and leaves MLS rules out. The same evidence serves a legislature that later writes access into statute.
Appendix A: Selected MindCast Works
Companion Paper
California Private Listing Law After Washington SSB 6091 — Broker Conduct Rules for Listing Visibility, Showing Access and Buyer Representation. The paper proposes the statute that would write access and representation rules into California law, and it supplies four of the Simulation Predictions applied here.
State Enforcement
Why Compass Needs Private Listings, The Inventory-Routing Premium — Compass, the Anywhere Merger, and the Multi-State Enforcement Window. The paper matches each state enforcer to the antitrust and consumer-protection law it already holds.
How State Attorney General Coalitions Form, Grow, and Hold. The paper supplies the coalition mechanics and two of the Simulation Predictions applied here.
Compass’s Interpretation of “Public Marketing” May Draw Antitrust Scrutiny from State Attorneys General. The paper lists the statutes that carry a state claim, describes the cross-state comparison and recommends a preservation demand as the first step.
Federal Inaction Has Elevated State Authority on Consumer Protection, Antitrust, and Market Integrity. The briefing lists the state tools available to an attorney general and estimates Compass’s share in three metropolitan markets.
Frameworks
The Chicago School Accelerated Part I, Coase and Why Transaction Costs ≠ Coordination Costs. The paper explains why parties who disagree about the object of a negotiation cannot bargain to a result.
Compass’s Coasean Coordination Problem Part I, How Private Exclusives Reshape Competition and Threaten MLS Stability. The paper identifies the MLS as the shared reference point that keeps the market complete for every buyer.
The Stigler Equilibrium- Regulatory Capture and the Structure of Free Markets. The paper explains why enforcement shared among many offices is harder to close than enforcement run through one.
The Dual Nash-Stigler Equilibrium Architecture. The paper describes outcomes that look stable and rest on coercion, missing information or absent enforcement.
The Skillman Moment as Analytical Rosetta Stone of the MindCast MLS Equilibrium Series. The paper supplies three questions an MLS board can use to test a rule demand.
Related Analysis
Compass Double-Sided Commissions — Consumer Policy Center Measures the Output, MindCast Models the System. The paper sets a consumer group’s report on both-sides commissions beside MindCast’s Seattle transaction data.
The Compass–Zillow Antitrust Litigation Arc Is Closed. Here Is What the Record Shows.. The paper reviews a private suit that ended without a decision on the merits.
Compass’s Coasean Coordination Problem Part III- Coordination Costs, MLS Governance and the Compass Litigation. The paper treats Compass’s claimed premium for pre-marketed listings as a cost to buyers.
State Power vs. Compass Private Exclusives. The paper sets out the state consumer-protection route.
From Inventory Control to Attention Control: The Compass Commission-Consolidation Model After First Look. The paper places the listing brokerage’s remaining advantage with buyers who arrive without an agent.
Compass’s Cross-Forum Contradictions. The paper collects the investor statements an access inquiry would cite.
Compass’s ‘Consumer Choice’ Rhetorical Framing as a Control Mechanism. The paper distinguishes two meanings of consumer choice.
The Compass–NWMLS Settlement Changed the Private Governor After Washington Changed the Governing Law. The paper shows that Washington’s statute carries the binding rule and the MLS agreement sits above it.
How the Zillow Complaint Reframes Compass v. NWMLS as a National Coordination Case. The paper explains the group-boycott claim a state reviewer would adapt.
Compass Plan B, Structural Circumvention After Washington SSB 6091. The paper maps the routes around a concurrent-marketing law.
Appendix B: External Sources
Primary Sources
California Regional Multiple Listing Service. CRMLS’s Formal Response. September 30, 2026.
Northwest Multiple Listing Service. “Northwest MLS Expands Listing Options”. August 31, 2026.
California Legislature. Assembly Bill 1776. Signed September 30, 2026 and effective January 1, 2027.
California Civil Code section 1088.
California Department of Real Estate. Consumer Alert: Changes to Buyer Representation and Compensation. November 2024.
Washington State Department of Licensing. News and Updates for Real Estate Brokers.
Compass, Inc. Fourth-quarter 2024 earnings exhibit, Form 8-K. Securities and Exchange Commission.
Compass, Inc. 2025 proxy statement, Form DEF 14A. Securities and Exchange Commission.
Compass, Inc. “Federal Court Ruling Strengthens Path to Nationwide Adoption of Three-Phased Marketing”. September 17, 2026.
Zillow. Complaint, Zillow v. Midwest Real Estate Data and Compass. Northern District of Illinois. May 12, 2026.
Eastern Railroad Presidents Conference v. Noerr Motor Freight, Inc., 365 U.S. 127 (1961).
Secondary Reporting
Brooklee Han. “Compass’s Reffkin gives MLSs an ultimatum: Change listing rules or face lawsuits”. HousingWire. September 30, 2026.
AJ LaTrace. “’We will spend millions’: Compass’ growing fight with MLSs explained”. Inman. September 30, 2026.
Jesse Williams. “Compass Threatens More Legal Action Against MLSs, with CRMLS Leading Opposition”. RISMedia. September 30, 2026.
Inman. “’Uncomfortable’ and ‘tense’: CMLS attendees push back on Reffkin pitch”. October 1, 2026.
Inman. “Zillow loses injunction battle with MRED, Compass over listing rules”. September 16, 2026.
Inman. “New York attorney general opens antitrust inquiry into Compass”. June 3, 2026.
HousingWire. “Federal court denies Zillow injunction, sends MRED claims to arbitration”. September 2026.
HousingWire. “Zillow alleges MRED, Compass conspired over private listings”. May 2026.
HousingWire. Report on the Compass and NWMLS trial schedule. 2025.
HousingWire. “Connecticut passes private listing network law”. June 2026.
HousingWire. “’Lawfare is now the norm’: MLS leaders brace for more legal battles”. October 2026.
Real Estate News. “The future of Zillow and Compass as ‘See It First’ goes live”. September 22, 2026.
Real Estate News. “Judiciary subcommittee summons Compass, MRED CEOs for briefing”. July 22, 2026.
The Real Deal. “’They want us to not enforce the rules’: CRMLS fires back at Compass’ legal threat in private listings spat”. October 1, 2026.
The Real Deal. “Compass to syndicate exclusive ‘Coming Soon’ listings on Redfin”. February 2026.
RISMedia. “Consumer Groups Target Zillow and Compass in Letter to State Attorneys General”. September 16, 2026.
Bloomberg Law. “DOJ Allows Compass-Anywhere Deal After Overruling Staff”. January 9, 2026.
Gibson Dunn. “California Approves Single-Firm Conduct Legislation”. September 30, 2026.
Crowell & Moring. “The COMPETE Act Becomes Law: What the New Antitrust Law Means for California Businesses”. 2026.
American Economic Liberties Project. “Monthly Monopoly Digest”. September 2026.
StockStory. “The 5 Most Interesting Analyst Questions From Compass’s Q1 Earnings Call”. June 2025.
