Kalshi Seeks Ninth Circuit En Banc Rehearing While Robinhood Files Separate SCOTUS Petition
Kalshi filed a petition for en banc rehearing at the Ninth Circuit on September 9, asking the full 11-judge court to overturn the August 28 3-0 panel ruling that Nevada can regulate its sports contracts as gambling. Simultaneously, Robinhood filed its own separate certiorari petition with the Supreme Court challenging the same Ninth Circuit ruling. The two platforms are pursuing parallel legal strategies from the same defeat: Kalshi seeking a better ruling at the Ninth Circuit first; Robinhood going directly to SCOTUS. New Jersey has already filed a SCOTUS petition from the Third Circuit's April ruling. There are now two separate cert petitions before the Supreme Court on the prediction market question.
Kalshi filed a petition for en banc rehearing at the Ninth Circuit on September 9, 2026, asking the full court — 11 judges rather than the 3-judge panel that ruled 3-0 on August 28 — to reconsider whether Nevada can regulate its sports event contracts as gambling. En banc review is the procedural step between a panel ruling and Supreme Court petition; it asks the full circuit to reconsider a panel decision where the losing party believes the ruling conflicts with established circuit precedent or creates a circuit split requiring full-court resolution. Kalshi's petition argues both: that the Ninth Circuit panel's ruling conflicts with the Third Circuit's April ruling, and that the 'exceptionally important question of federal preemption' requires the full court's guidance before the question goes to SCOTUS. Ninth Circuit en banc petitions are granted in roughly 1-2% of cases — a low grant rate, but higher for cases involving acknowledged circuit splits on federal statutory interpretation.
Robinhood filed its own separate certiorari petition with the Supreme Court on the same day — September 9 — seeking SCOTUS review of the same Ninth Circuit ruling without waiting for en banc consideration. The two platforms are pursuing parallel strategies from the same August 28 defeat. Kalshi's approach: exhaust the Ninth Circuit process first, potentially obtaining a better ruling at the en banc level that either reverses the panel or produces a narrower adverse ruling; then petition SCOTUS if needed. Robinhood's approach: go directly to SCOTUS, treating the circuit split as already established and the en banc process as unnecessary delay. Neither approach is wrong as a strategic matter, and the two can coexist: Robinhood's SCOTUS petition can proceed while Kalshi's en banc petition is pending; SCOTUS will likely hold Robinhood's petition pending resolution of either the en banc process or New Jersey's already-filed petition from the Third Circuit loss.
The SCOTUS petition landscape has now expanded significantly. New Jersey filed the first prediction market cert petition on September 2 — asking SCOTUS to review the Third Circuit's April ruling that went against NJ and for Kalshi. Robinhood's September 9 petition asks SCOTUS to review the Ninth Circuit's August 28 ruling that went against Robinhood (and Kalshi) and for Nevada. The two petitions approach the same ultimate question — does the CEA preempt state gambling regulation of prediction market sports contracts? — from opposite circuit outcomes. SCOTUS can consolidate multiple cert petitions raising the same question, brief them together, and issue one ruling. The more petitions that arrive, the harder it becomes for SCOTUS to avoid resolving the question; the Court is unlikely to simultaneously grant NJ's petition from the Third Circuit ruling and deny Robinhood's from the Ninth Circuit ruling when both raise the same statutory interpretation question. At least three prediction market cert petitions are now anticipated: NJ (Third Circuit), Robinhood (Ninth Circuit), and whatever Kalshi files after the en banc result.
The practical effect of Kalshi's en banc petition is a pause on Kalshi's own SCOTUS timeline. If the Ninth Circuit grants en banc review, the en banc court will schedule full briefing and argument — a process that can take six to twelve months. If the en banc panel then rules differently from the three-judge panel (possible, but not likely given the 3-0 margin and the strength of the panel's reasoning), the circuit split may be resolved at the circuit level, reducing the SCOTUS urgency. If the en banc panel affirms the three-judge ruling, Kalshi would have a stronger petition to SCOTUS with a full-circuit ruling rather than just a three-judge panel. If the Ninth Circuit denies en banc review — the most likely outcome statistically — Kalshi can immediately petition SCOTUS using the same arguments it made to the en banc court. Either way, Kalshi's en banc petition is a lower-risk first move than going straight to SCOTUS: it costs little if denied, potentially helps if granted, and preserves the SCOTUS option regardless of outcome.
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