🔴 Top Stories
NYSE and Cboe BZX adopt mandatory corporate-action halts ahead of 23/5 trading
NYSE (Rule 7.18) and Cboe BZX (Rule 11.29) each filed immediately effective, 'non-controversial' rule changes requiring market-wide regulatory halts in their listed securities undergoing any of nine corporate action types \u2014 symbol/CUSIP changes, splits, large stock dividends, de-SPACs, spin-offs, mergers, security-type changes, plus a catch-all \u2014 because the shift to near-continuous 23/5 trading eliminates the overnight processing window. The filings differ mainly in reopening mechanics: NYSE halts before the 9:00 p.m. ET overnight session and reopens via a Trading Halt Auction after 9:30 a.m. the next morning, while BZX reopens via a Halt Auction at 8:00 a.m. ET, with BZX pointing to a December 6, 2026 launch target. Both took effect under Rule 19b-4(f)(6) without SEC approval, and suspension looks unlikely given NYSE Arca's identical filing already cleared and Nasdaq is adopting matching rules.
IEX RELEVANT All venues including IEX must honor these halts, and the standardized regime further entrenches primary listing exchanges' control over when extended-hours and overnight trading can occur \u2014 a structural lever IEX lacks as a non-primary listing market.
Combined from 2 filings
MEMX adopts 23/5 rules while Nasdaq waives Night Session port fees
MEMX filed immediately effective rules to trade equities and ETPs 23 hours a day, five days a week \u2014 adding a 9:00 p.m.\u20134:00 a.m. Overnight Trading Session and an 8:00 p.m. maintenance pause that cancels resting orders \u2014 copying Cboe EDGX's approved model, though it cannot launch until the SIPs can disseminate overnight data and it makes a confirming filing. Separately, Nasdaq clarified port pricing for its roughly December 6, 2026 Night Session, waiving fees for the first five ports of each type per MPID plus five test-facility ports. Together the filings show incumbents both building the rulebook and removing cost barriers to overnight onboarding.
IEX RELEVANT With MEMX joining EDGX, Nasdaq, NYSE Arca and 24X and Nasdaq making overnight connectivity effectively free, 23/5 trading is becoming table stakes, forcing IEX to decide whether to extend hours or cede a growing slice of retail and international flow.
Combined from 2 filings
🔵 IEX Competitive Intel
NYSE Arca and NYSE American file to list binary KPI options
NYSE Arca and NYSE American both filed proposals to list 'binary KPI options' \u2014 all-or-nothing $1-payout contracts settling on whether an issuer's reported earnings metric (EPS, revenue, segment sales, subscriber counts) hits a strike level \u2014 with Arca specifying 22 large-cap underliers including Apple, Nvidia, Tesla and SpaceX. The filings follow near-identical pending proposals from Cboe and MEMX and represent exchanges' bid to pull event-contract/prediction-market flow from CFTC-regulated venues like Kalshi onto SEC-regulated options markets. The SEC has only published both for comment, starting a 45-to-240-day clock; the novel questions of whether a contract on a financial metric is a 'security,' which clearing agency applies, and insider-trading risk around earnings make extended proceedings likely.
IEX RELEVANT Signals that every major exchange group is racing to capture event-contract revenue inside the securities framework, a growth avenue IEX has no presence in and whose regulatory outcome will set the template for all exchanges.
Combined from 2 filings
2026-09-18
NYSE Arca
Notice of Filing of a Proposed Rule Change To Permit the Listing of Binary KPI Options
2026-09-18
NYSE American
Notice of Filing of a Proposed Rule Change To Permit the Listing of Binary KPI Options
Cboe's four equities exchanges add 'Regular 'til Post Market' time-in-force
Cboe BZX, BYX, EDGA and EDGX each added a new time-in-force, 'Regular 'til Post Market' (RTP), letting a member submit a single limit order that works through regular hours and automatically remains live into the 4:00-8:00 p.m. post-close session, instead of sending separate orders or using a broader TIF that also covers pre-market. All four were filed as noncontroversial with the SEC waiving the 30-day operative delay, so they are live now with rollout planned for early Q4 2026; Nasdaq and NYSE Arca already offer equivalent functionality. The filings differ only in the rule numbers amended (11.1/11.6/11.7/11.8 on the EDG books versus 11.1(a)/11.9(b)/11.23/11.24 on BZX and BYX) and BZX's clarification that RTP orders are treated like RHO orders in auctions.
IEX RELEVANT A modest but coordinated convenience edge across all four Cboe venues for retaining resting interest into after-hours, part of the broader extended-hours competition IEX may need to match in its own TIF suite.
Combined from 4 filings
2026-09-18
Cboe EDGX
Notice of Filing and Immediate Effectiveness of a Proposed Rule Change To Amend Exchange …
2026-09-15
Cboe EDGA
Notice of Filing and Immediate Effectiveness of a Proposed Rule Change To Amend Exchange …
All equity SROs harmonize Level 3 circuit-breaker reopen time at 4:00 a.m. ahead of 23/5 trading
NYSE, NYSE American, NYSE Arca, NYSE National, NYSE Texas and MIAX Pearl each filed immediately effective amendments (Rules 7.12/7.12E/7.12-E and MIAX Rule 2628) clarifying that after a Level 3 market-wide circuit breaker halt trading cannot resume until at least 4:00 a.m. ET the next trading day. Without the fix, the existing 'remainder of the trading day' language would have allowed the new 9:00 p.m. ET overnight sessions launching December 6, 2026 to reopen the same evening, cutting short the intended cooling-off period. The changes are industry-coordinated with all equity SROs and FINRA, took effect on filing with only a 60-day SEC suspension window, and are operationally a no-op versus today's practice; the filings differ only in rule numbering and which affiliate operates an overnight session.
IEX RELEVANT IEX will need to file the same conforming MWCB amendment to stay harmonized, and the coordinated wave confirms the 23/5 overnight regime is firmly on track for December 6, 2026.
Combined from 6 filings
2026-09-18
NYSE
Notice of Filing and Immediate Effectiveness of Proposed Rule Change To Amend Rule 7.12 C…
2026-09-18
NYSE American
Notice of Filing and Immediate Effectiveness of Proposed Rule Change To Amend Rule 7.12E …
2026-09-18
NYSE Arca
Notice of Filing and Immediate Effectiveness of Proposed Rule Change To Amend Rule 7.12-E…
2026-09-18
NYSE National
Notice of Filing and Immediate Effectiveness of Proposed Rule Change To Amend Rule 7.12 C…
NYSE Arca is tweaking its Retail Tier pricing: it restores a 'time-in-force of Day' qualifier so that only Day retail orders matching against same-MPID retail contra-side orders trade free of fees and credits, and it pulls midpoint (MPL) and Discretionary Pegged orders carrying a retail modifier out of the retail fee schedule so they instead pay standard removal rates ($0.0010/$0.0030 per share). The change took effect immediately upon filing under the fee-filing rule, so it is already live; the SEC is only taking comment and retains a 60-day window to suspend it, which is unlikely for a narrow pricing adjustment like this. Practically, retail brokers routing non-Day retail orders or retail-flagged midpoint/pegged orders to Arca will see slightly different economics, while the headline retail rebate tiers are unchanged.
IEX RELEVANT Arca is fine-tuning retail-flow pricing incentives — including for midpoint and discretionary pegged orders that compete with IEX's midpoint and D-Peg/D-Limit liquidity — so it marginally affects where retail and midpoint flow gets routed.
IEX is expanding its new External Distribution Rebate — which pays 75% of subscription fees back to firms that sign up brand-new subscribers to IEX's real-time TOPS/DEEP/DEEP+ feeds — so that extranet providers (connectivity vendors like network carriers that carry IEX data but aren't themselves data subscribers) can also earn it. The goal is to turn extranets into a distribution sales channel and grow the installed base of IEX market data users. The fee change was effective immediately upon filing and went live September 1, 2026; the SEC is merely publishing it for comment and retains a 60-day window to suspend it, which is uncommon for routine distribution incentives, so in practice extranet providers can start earning rebates now.
IEX RELEVANT This is IEX's own filing: it broadens the channel for growing paid subscriptions to IEX proprietary data feeds by paying extranet providers to recruit new subscribers, supporting IEX's market data revenue and footprint against Cboe and NYSE distribution-credit programs.
IEX previously filed (SR-IEX-2026-19) to allow pegged orders to trade during pre-market and post-market sessions, and committed to announce the go-live date via Trading Alert within 90 days (by October 8, 2026). This filing simply pushes that announcement deadline out 60 days to December 7, 2026, to give IEX time to finish its normal technology deployment steps. The SEC accepted it as non-controversial and waived the 30-day waiting period, so it is effective immediately — nothing about the substance of extended-hours pegged order trading changes, only the timing of the launch announcement.
IEX RELEVANT This is IEX's own filing, delaying the rollout announcement for pegged order support in pre- and post-market sessions — a modest extension to IEX's extended-hours product capability.
NYSE American is updating its clearly erroneous execution (CEE) rule to account for the new Overnight Price Bands the SEC approved under the LULD Plan in August 2026, ahead of industry-wide 23/5 trading starting December 6, 2026. The change means trades executed within the overnight price bands generally can't be busted after the fact, mirroring how the rule already works during regular hours; only stocks not covered by LULD (e.g., rights and warrants) remain reviewable, using off-hours numerical guidelines. Filed as immediately effective, so it takes effect without SEC approval (the SEC retains a 60-day suspension window that is unlikely to be used), and all other exchanges and FINRA are expected to file identical proposals.
IEX RELEVANT IEX will need to make the same conforming CEE rule change for overnight trading, and the harmonized trade-break framework is a building block of the December 2026 23/5 industry launch that IEX must plan for competitively.