SCOTUS September 28 Long Conference: First Opportunity to Take the Prediction Market Case
The Supreme Court's September 28 'long conference' — the Court's first conference of the new term — is the first opportunity for the justices to consider whether to grant certiorari in the prediction market cases currently on the docket. New Jersey filed its petition on September 2 (from the Third Circuit loss); Robinhood filed on September 9 (from the Ninth Circuit loss). Kalshi has 30 days to respond to the New Jersey petition. Polymarket prices a 46% chance SCOTUS accepts a prediction market case by year end. Most analyst projections place a cert decision between November and December 2026.
The Supreme Court of the United States holds its first conference of the new October term on September 28, 2026 — the 'long conference,' at which the justices work through the backlog of cert petitions that accumulated over the summer recess. Two prediction market petitions are on the docket: New Jersey's petition (filed September 2) arising from the Third Circuit's April ruling for Kalshi, and Robinhood's petition (filed September 9) arising from the Ninth Circuit's August 28 ruling against Kalshi. Whether either petition is considered at the September 28 conference depends on the timing of Kalshi's response briefs. Kalshi has 30 days from when each petition was docketed to file a response, which means Kalshi's response to New Jersey's petition may be due around October 2. If Kalshi has not responded by September 28, the conference may distribute the petitions to the October conference schedule rather than acting on them immediately. The Court could also request that Kalshi waive its response, which would allow the petitions to be considered without it.
Even if the long conference cannot formally act on the petitions, September 28 is the first day the justices are back together as a court and discussing the cert docket — and the prediction market cases are already the most discussed pending federal question in the legal commentary. The combination of an explicit circuit split (Third Circuit vs. Ninth Circuit on the same preemption question), high economic stakes ($14B+ weekly contract volume), active enforcement litigation in ten states, and multiple pending petitions creates the standard conditions under which the Supreme Court grants cert. Legal commentators who track SCOTUS cert patterns place the probability of at least one petition being granted at between 60-70%. Polymarket prices the probability at 46% by year end, which reflects both the genuine possibility and the timing uncertainty introduced by Kalshi's pending en banc petition at the Ninth Circuit.
Kalshi's en banc petition — filed simultaneously with Robinhood's SCOTUS petition on September 9 — creates a procedural interaction that may affect the SCOTUS timeline. If the Ninth Circuit grants en banc review, the August 28 panel ruling is vacated and there is no longer a live Ninth Circuit judgment to petition from. Robinhood's SCOTUS petition, which is based on the August 28 ruling, would lose its foundation, and the Ninth Circuit would essentially reset its ruling process with the full 11-judge panel. This outcome — while unlikely at the 1-2% historical en banc grant rate — would temporarily narrow the circuit split to only the Third Circuit, which ruled for Kalshi, with no adverse circuit ruling to conflict with it. SCOTUS is less likely to grant cert when only one circuit has ruled on a question; the circuit split is what makes the case ripe for resolution. The Ninth Circuit is expected to rule on the en banc petition within weeks to months.
From the platforms' perspective, a SCOTUS cert grant is the best available outcome. A favorable SCOTUS ruling would resolve the preemption question nationally, ending the state enforcement litigation in all 10+ jurisdictions simultaneously. A cert denial would leave the circuit split in place and the legal uncertainty unresolved, and the litigation in individual states — Massachusetts, Connecticut, Michigan, New York, Nevada, Washington, Wisconsin, Rhode Island, New Mexico, Missouri — would need to proceed to final judgment in each circuit, potentially producing additional conflicting rulings. For Kalshi, the October 2026-June 2027 SCOTUS term is the critical window: if the Court grants cert this fall and briefs are filed over the winter, oral arguments would be in early 2027 and a decision by June 2027. That timeline would resolve the national legal question before the 2027 NFL season, before any midterm-related state AG turnover takes effect, and before Kalshi's platform growth hits the next inflection point where state enforcement costs become a serious operational constraint.
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Recent updates
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