Will Compass receive a favorable ruling (or settlement) in the Compass v. Zillow private exclusives lawsuit by September 30, 2026?

The preliminary injunction denial is a substantively meaningful negative signal. The judge found Compass's monopoly power arguments unconvincing, specifically citing declining Zillow market share and new entrants. While PI denial does not determine trial outcome, the judge's reasoning on market definition and monopoly power will likely persist at trial. Additionally, the September 30 deadline creates significant timeline risk: even if the June trial proceeds on schedule, complex antitrust trials take weeks to try, and post-trial motions could push any verdict past the deadline. Settlement is possible but Zillow has weak incentives to settle favorably given the PI win.

Antitrust litigation favors defendants statistically — plaintiffs face high evidentiary burdens under both Section 1 and Section 2 of the Sherman Act. The Section 2 monopoly claim is particularly weakened by the judge's preliminary finding that Zillow's market share is declining due to competitive entry. The Section 1 conspiracy claim requires proving an agreement in restraint of trade, which is difficult when Zillow is acting unilaterally via its own platform policy. The 'no resolution by Sep 30' clause adds substantial probability mass to NO, as federal litigation timelines routinely slip. I estimate a roughly 10% chance of favorable verdict by Sep 30, 8% chance of favorable settlement, and 2% chance of dismissal in Compass's favor.

While the PI denial is a negative signal, the merits at trial may differ: the PI standard requires showing 'likelihood of success,' and the judge's ruling focused on one element (monopoly power) that could be addressed with better evidence at trial. The DOJ's interest in the Clear Cooperation policy could create a favorable regulatory backdrop. More importantly, settlement dynamics are unpredictable — Zillow may calculate that the litigation cost and reputational risk of a full trial exceed the value of maintaining the ban, especially if DOJ signals shift. I weight settlement probability somewhat higher than other runs at around 12-15%, bringing total YES to roughly 25%.

The denied preliminary injunction is the strongest signal available. The judge specifically found Compass's monopoly power arguments unconvincing, which directly undermines the Section 2 claim. Federal antitrust trials with the plaintiff losing at the PI stage have a poor track record of ultimate success. The September 30 deadline further compresses the probability — even with a June trial date, antitrust trials are complex and verdicts may take months after trial concludes. Settlement is the most plausible YES pathway, but Zillow's bargaining position strengthened after the PI ruling.

Breaking down the YES scenarios: (1) Trial verdict favoring Compass by Sep 30 — requires on-schedule June trial, Compass winning on merits, and verdict by Sep 30, probability roughly 8-10%; (2) Settlement allowing private exclusives — Zillow has limited incentive but litigation uncertainty remains, probability roughly 10%; (3) Case dismissed favorably — unlikely at this stage, roughly 2-3%. Total YES approximately 22%. The 'declining market share' finding is particularly damaging because it attacks the threshold requirement for a Section 2 claim — if Zillow lacks monopoly power, the entire monopolization theory fails regardless of conduct analysis.

The market question has a built-in asymmetry: YES requires affirmative favorable resolution by a fixed date, while NO captures all other outcomes including delay. In federal litigation, delay is the default — trial dates slip, motions extend timelines, and judges manage crowded dockets. Even optimistically assuming a 35% chance Compass ultimately prevails on the merits, the probability of that happening by Sep 30 is substantially lower. The PI denial further shifts the merits probability downward. Compass's 340,000-agent network argument is compelling as a harm story but does not resolve the monopoly power question that the judge already flagged.

PI denial is a strong negative signal. Judge found declining Zillow market share, undermining monopoly claim. September deadline adds heavy NO weight since litigation delays are common. Settlement possible but Zillow has little incentive after winning PI motion.

Antitrust plaintiffs face high burdens. The PI ruling specifically found declining market share, which is devastating to Section 2. Even if trial starts in June, verdict by September is not assured. The most likely outcome is no resolution by the deadline, which resolves as NO.

Three paths to YES all have low probability: favorable verdict (needs trial on time plus win), settlement (Zillow has no incentive), dismissal (unlikely at this stage). The combined probability is around 18%. DOJ interest provides modest tailwind but is unlikely to change dynamics by September.