Listings Timeline

  • Auctions Availability in the IEX Testing Facility ("ITF")
    • TOPS v1.6 Deployed in the ITF
    • DEEP v1.0 and TOPS v1.6 Begin Publishing Auction Information and Security Directory Messages in the ITF for Test IEX-Listed Securities
  • Opening Process for Non-IEX-Listed Securities
  • 1st Member Testing Opportunity (Production Environment)
  • Market Maker Peg Order Type Available in the ITF
  • TOPS v1.6 Launched in the Production Environment
  • 2nd Member Testing Opportunity (Disaster Recovery Environment)
  • Auctions Available in Production for Test IEX-Listed Securities
    • Test IEX-Listed Securities (ZIEXT, ZEXIT, ZXIET)
    • DEEP v1.0 and TOPS v1.6 Begin Publishing Auction Information and Security Directory Messages in the Production Environment for Test IEX-Listed Securities
  • 3rd Member Testing Opportunity (Production Environment)
  • Market Maker Peg Order Type Available in the Production Environment
  • 4th Member Testing Opportunity (Production Environment)
  • Pending SEC Approval, IEX Launches as a Primary Listing Exchange, Phase-in Period Begins

As a reminder, in accordance with Regulation SCI, IEX will conduct testing of its Business Continuity and Disaster Recovery Plans during the planned SIFMA industry-wide test on Saturday October 14, 2017, during which time IEX will offer testing opportunities of the auction process from the DR environment. For more information, please review IEX Trading Alert #2017 - 002.

Listings FAQ

Topics

Auctions

Will IEX conduct auctions for IEX-listed securities?

The IEX Auction Process provides electronic price discovery mechanisms that efficiently match orders in IEX-listed securities at a single price using a double auction. These auctions enable IEX participants to execute against On-Open and On-Close interest at IEX. They also allow for participation in IEX corporate initial public offerings ("IPOs"), new issues, auctions resulting from security halts, and auctions resulting from LULD trading pauses. During the auction process, IEX will calculate and disseminate current price, size, imbalance information, auction collar information, and other relevant information about upcoming auctions via IEX Auction Information.

The IEX Opening/Closing Auction has been designed to efficiently maximize the number of shares executed at a single price for securities during the Regular Market Session open/close, respectively, while minimizing the opportunities for information leakage within the NBBO. The IEX IPO/Halt Auction provides a mechanism that has been designed to allow participants to match a maximum number of shares at a single price for IPOs, new issues, and securities coming out of a trading halt based on supply and demand. The IEX Volatility Auction provides a mechanism that has been designed to allow Users to match a maximum number of shares at a single price for securities coming out of an LULD trading pause based on supply and demand.

How do IEX Opening and Closing Auctions work?

IEX accepts On-Open and On-Close order types that are executable only during the Opening or Closing Auction, respectively.

  • Leading up to an open or close, IEX disseminates information about any order imbalance that exists among orders on the Opening or Closing Auction Book, along with an indicative opening or closing price.
  • In the auction process, the Opening or Closing Auction Book and the IEX Continuous Book are brought together to create a single IEX opening or closing price.
  • IEX opening and closing prices are distributed to the Consolidated Tape immediately after the auction occurs.

What are the current thresholds for establishing the Opening and Closing Auction prices?

The Opening and Closing Auction threshold is the greater of $0.50 or 10%.

How are the thresholds applied to the Opening/Closing Auction Collar?

The threshold of 10% is utilized to calculate a price range for the auction, also known as the auction collar. 10% of the midpoint of the Reference Price Range (generally the Protected National Best Bid and Offer (“Protected NBBO”) Midpoint) (with a minimum of $0.50) is added to the National Best Offer that is a protected quotation (“Protected NBO”) and subtracted from the National Best Bid that is a protected quotation (“Protected NBB”), when there is a valid Protected NBBO, to establish the threshold price range.

For example, if the Protected NBB/NBO is $10.00 x $11.00, then the Protected NBBO Midpoint equals $10.50 and the threshold value is 10%: 10% x $10.50 = $1.05. This value is then added to the Protected NBO and subtracted from the Protected NBB to obtain the auction’s threshold range:

  • Protected NBB: $10.00 - $1.05 = $8.95
  • Protected NBO: $11.00 + $1.05 = $12.05

Therefore, in this example, the auction can occur within the prices of $8.95 and $12.05. This means $8.95 is the lowest price at which the auction can occur and $12.05 is the highest price at which it can occur. The threshold range (i.e., auction collar) is dynamic; as the Protected NBBO changes, the threshold price range changes.

What time does the Opening and Closing Auction execute?

At 9:30 a.m. ET (note that all times are Eastern Time), the Opening Auction is initiated and the Opening Auction Book and the IEX Continuous Book are brought together to create a single IEX Opening Auction. IEX opening prices are distributed to the Consolidated Tape immediately after the Opening Auction.

At 4:00 p.m., the Closing Auction is initiated and the Closing Auction Book and the IEX Continuous Book are brought together to create a single IEX Closing Auction. IEX closing prices are distributed to the Consolidated Tape immediately after the Closing Auction.

  • As the Closing Auction completes in each stock, after hours trading commences in that stock.

IEX will disseminate IEX Auction Information every one second between the Lock-in Time (9:28 a.m. / 3:50 p.m. ET) and the auction match for the Opening/Closing Auction, and during the Display Only Period for the IPO/Halt/Volatility Auction. IEX Auction Information is available to subscribers of the IEX Top of Book Quote and Last Sale feed ("TOPS"), the IEX Depth of Book and Last Sale feed ("DEEP"), and will also made available to other market participants by various market data vendors.

IEX Auction Information will also be available on the IEX public website via various IEX apps and the IEX API.

Firms may also receive portions of IEX Auction Information via the CTS binary feed once it launches. In the binary CTS feed, the CTA is introducing a new Auction Status message which will contain auction collar and extension information.

What information about the Opening and Closing Auction is disseminated leading up to the open and close?

Between 9:28 and 9:30 a.m. and 3:50 and 4:00 p.m., IEX disseminates the following information every one second via DEEP, TOPS, the IEX API, and the IEX public website.

  • Reference Price: The price within the Reference Price Range (generally, the Protected NBBO) at which paired shares are maximized, unexecuted shares are not traded through, and the distance from the Volume Based Tie Breaker is minimized, in that order.
  • Indicative Clearing Price: The price within the auction collar at which orders in the IEX Opening / Closing Auction Book and Continuous Book would clear against each other.
  • Auction Book Clearing Price: The price at which orders in the IEX Opening / Closing Auction Book would clear against each other.
  • Paired Shares: The number of shares on the IEX Opening / Closing Auction Book that IEX is able to pair off at the Reference Price.
  • Imbalance Shares: The number of shares on the IEX Opening / Closing Auction Book that would remain unexecuted at the Reference Price.
  • Imbalance Side: The side of the imbalance: B = buy-side imbalance; S = sell-side imbalance; N = no imbalance.
  • Collar Reference Price: The Volume Based Tie Breaker (generally, the Protected NBBO Midpoint), which was used in calculating the auction’s threshold range.
  • Lower Auction Collar: The lower threshold of the auction collar, which is the lowest price at which the auction can occur and the most aggressive price accepted for sell orders eligible for the IEX Opening (Closing) Auction Book after 9:28 a.m. (3:50 p.m.) (Lock-in Time).
  • Upper Auction Collar: The upper threshold of the auction collar, which is the highest price at which the auction can occur and the most aggressive price accepted for buy orders eligible for the IEX Opening (Closing) Auction Book after 9:28 a.m. (3:50 p.m.) (Lock-in Time).

DEEP and TOPS are available via a wide array of market data vendors and service bureaus, and also directly from IEX. The IEX API is available from the IEX public website. Additionally, IEX Auction Information is available on the IEX public website. All auction information is provided free of charge. To learn more, please visit IEX Market Data or IEX Apps.

Which order types are eligible for Opening and Closing Auctions?

Opening Auction

Queued Regular Hours Orders (Opening Auction Book)

  • Executable from 9:30 a.m. to 4:00 p.m., including during the Opening Auction.
  • Includes limit DAY or GTX orders, and non-routable market DAY orders queued before the auction.
  • Limit orders received after 9:28 a.m. (Lock-in Time) are accepted for the Opening Auction, subject to the hyper-aggressive price restrictions. Limit orders are rejected after 9:29:50 a.m. (Lock-out Time) until the market opens.
  • Market Orders received after 9:28 a.m. will be rejected until the market opens.

On-Open Orders (Opening Auction Book)

  • Executed only during the Opening Auction.
  • Market-On-Open (“MOO”) orders must be received prior to 9:28 a.m.
  • Limit-On-Open (“LOO”) orders received after 9:28 a.m. are accepted for the Opening Auction, subject to the hyper-aggressive price restrictions. LOO orders are rejected after 9:29:50 a.m.

System Hours Orders (Continuous Book)

  • Executable from 8:00 a.m. to 5:00 p.m., including during the Opening Auction.
  • Includes limit SYS or GTT orders. No market orders execute during pre/post-market hours.
  • Lock-in and Lock-out Time restrictions do not apply to orders on the Continuous Book.

Closing Auction

On-Close Orders (Closing Auction Book)

  • Allow investors to specifically request an execution at the closing price.
  • Accepted beginning at 8:00 a.m.; executable only during the Closing Auction.
  • Market-On-Close (“MOC”) orders must be received prior to 3:50 p.m. (Lock-in Time).
  • Limit-On-Close (“LOC”) received after 3:50 p.m. are accepted for the Closing Auction, subject to the hyper-aggressive price restrictions. LOC orders are rejected after 3:59:50 p.m. (Lock-out Time).

Regular Hours Orders and System Hours Orders (Continuous Book)

  • Posted and available for execution immediately during the Regular Market Session, and may participate in the Closing Auction.
  • Includes limit DAY, GTX, SYS, and GTT orders.
  • Includes pegged orders.
  • Lock-in and Lock-out Time restrictions do not apply to orders on the Continuous Book.

What are the hyper-aggressive restrictions enforced after the Lock-in Time of the Opening and Closing Auction?

Hyper-aggressive Auction Orders are rejected after the Lock-in Time for the Opening and Closing Auctions. The restriction applies to LOO orders and limit orders with a TIF of DAY or GTX received after 9:28 a.m. for the Opening Auction, as well as LOC orders received after 3:50 p.m. for the Closing Auction. Specifically, such buy (sell) orders priced above (below) the latest Upper (Lower) Auction Collar are rejected after the Lock-in Time. Note that MOO, market DAY, and MOC orders are also considered Hyper-aggressive Auction Orders and are rejected after the applicable Lock-in Time. Orders accepted between the Lock-in Time and the Lock-out Time are price setting in IEX Auctions, and are not treated as imbalance only.

Do paired shares and imbalance shares include orders entered after the Lock-in Time of the Opening and Closing Auction?

Yes. Specifically, LOO orders and limit orders with a TIF of DAY or GTX accepted after 9:28 a.m. for the Opening Auction, as well as LOC orders accepted after 3:50 p.m. for the Closing Auction are included in the number of paired shares and imbalance shares.

How is the execution priority of non-displayed orders on the IEX Continuous Book determined after the Opening and Closing Auction pricing process is complete?

To minimize information leakage of non-displayed orders resting within the spread, IEX uses a unique method to calculate the auction price, as well as the Indicative Clearing Price after the Lock-in Time. Non-displayed orders on the Continuous Book with a resting price within the Reference Price Range (generally, the Protected NBBO) are priced to the Protected NBBO – sell orders are priced to the Protected NBO and buy orders are priced to the Protected NBB – when determining the auction price, but remain ranked and eligible to execute during continuous trading and in the auction at their resting price. After the auction price is calculated, non-displayed orders are treated the same as displayed limit orders at their resting price, if any, with non-displayed priority, and without updating their timestamp used for time priority.

Is short selling permissible in the Opening and Closing Auction?

Yes, subject to applicable short sale rules.

Is the Manning Rule applicable to the Opening and Closing Auction?

Yes. The Manning Rule and all other market rules that pertain to the regular trading day apply to the IEX Opening and Closing Auction. In particular, when determining its Manning Rule obligations, a market participant must consider executions that result from the Opening and Closing Auctions since those executions occur during normal trading hours.

Does IEX guarantee Market-On-Close (“MOC”) orders in the Closing Auction?

No, the Opening and Closing Auctions provide unparalleled transparency which encourages market participants to provide necessary liquidity to offset any market order imbalance. LOC orders continue to be accepted after the Lock-in Time and may offset any imbalance until the Lock-out Time. Orders on the IEX Continuous Book are accepted until the auction and may offset any imbalance as well.

When are Regular Hours Orders too late to queue for the Opening Auction?

Regular hours orders received after 9:28 a.m. are accepted for the Opening Auction, subject to the hyper-aggressive price restrictions. Non-routable market orders with a TIF of DAY received after 9:28 a.m. and limit orders with a TIF of DAY or GTX received after 9:29:50 a.m. are too late to participate in the Opening Auction. Late orders are rejected after the applicable cut-off described above and must be resubmitted after the market opens.

If a firm sends in a MOO/MOC or LOO/LOC order after the Lock-in Time, is it rejected?

  • MOOs (MOCs) entered after the Lock-in Time at 9:28 a.m. (3:50 p.m.) are not accepted.
  • LOOs (LOCs) entered after the Lock-in Time at 9:28 a.m. (3:50 p.m.) are accepted for the Opening (Closing) Auction, subject to the hyper-aggressive price restrictions.
  • LOOs (LOCs) entered after the Lock-out Time at 9:29:50 a.m. (3:59:50 p.m.) are not accepted.

If a firm sends in a MOO/MOC or LOO/LOC order that does not get executed, will they receive a cancellation message?

Yes. A cancellation message will be returned to the firm after the auction occurs.

Which price is used to execute On-Open / On-Close orders? What happens for market and limit orders?

The auction process considers all orders on the IEX Book and the Reference Price Range (generally, the Protected NBBO) at the time of the auction. Non-displayed orders on the Continuous Book with a resting price within the Reference Price Range are priced to the Protected NBBO – sell orders are priced to the Protected NBO and buy orders are priced to the Protected NBB – when determining the auction price, but remain ranked and eligible to execute in the auction at their resting price. The auction price is based on the following steps:

  1. Maximize the number of shares executed.
  2. Do not trade through unexecuted orders.
  3. Minimize the distance from the Volume Based Tie Breaker (the midpoint of the Reference Price Range).

The Opening Auction price determines the IEX Official Opening Price for each stock that has an auction. If a stock does not have an Opening Auction, the IEX Official Opening Price is determined by the first regular way last-sale eligible trade reported by IEX at or after 9:30 a.m., when regular trading hours begin.

The Closing Auction price determines the IEX Official Closing Price for each stock included in the Closing Auction. If a stock does not have a closing auction, the last regular way last-sale eligible trade reported by IEX prior to 4:00 p.m. is used as the IEX Official Closing Price.

Do IEX Auctions access liquidity from other venues?

No. Only interest on the IEX Book is eligible to participate in IEX Auctions.

Is there special processing for odd lot orders?

Odd lots follow regular IEX processing.

Can pegged orders participate in the Closing Auction? And if so, can Primary and Discretionary Peg orders exercise discretion to participate in the Closing Auction?

Yes, if pegged orders reside on the IEX Continuous Book, they will participate in the Closing Auction at their current resting price. Yes, Primary and Discretionary Peg orders to buy (sell) may exercise price discretion up (down) to the Closing Auction price, except during periods of quote instability. When exercising price discretion, such orders are ranked behind any non-displayed interest at the auction price for the duration of the Closing Auction. If multiple orders are exercising price discretion during the Closing Auction, they maintain their relative time priority at the auction price. On-Close orders cannot be pegged or exercise discretion.

Operational Logistics

How can participants identify when their execution occurred in an IEX Auction?

IEX will populate TradeLiquidityIndicator (FIX tag 9730) and LastLiquidityInd (FIX tag 851) with new values to provide Users with liquidity details for the new trading events on the Exchange:

An execution that occurred during the Opening Match for non-IEX-listed securities will look much like an execution from an IEX Auction.

TradeLiquidityIndicator (FIX tag 9730) is used, in conjunction with LastMkt (FIX tag 30), to determine trading costs and characteristics of the trade. On Wednesday, August 23, 2017, IEX will begin to utilize the Opening Match value (9730=X), and on Friday, September 15, the Exchange will begin to utilize the Opening, Closing, Halt/Volatility, and IPO Auction values (9730=[O,C,H,N], respectively). For further information, please see the IEX FIX Specification.

Tag 9730 Values

  • I=Continuous trade on IEX
  • S=Self-matched trade on IEX
  • L=Trade on IEX involved displayed liquidity
  • X=Opening Match on IEX
  • O=Opening Auction on IEX
  • C=Closing Auction on IEX
  • H=Halt / Volatility Auction on IEX
  • N=IPO Auction on IEX

Last Liquidity Indicator (FIX tag 851) is provided to identify whether a User's order execution at IEX resulted from liquidity provision, removal, routing, or a single-price cross (e.g., an auction). On Wednesday, August 23, 2017, IEX will begin to utilize the new value (851=4) to identify when order execution resulted from a single-price cross.

Tag 851 Values

  • 1=Added Liquidity
  • 2=Removed Liquidity
  • 3=Routed
  • 4=Auction
  • 9=Removed Liquidity on Recheck

Usage examples:

  • Single-price Cross Executions on IEX (used in conjunction with FIX tag 851=4)
    • X is returned identifying a trade in the Opening Match of a non-IEX-listed security
    • OL is returned identifying a trade in the Opening Auction involving displayed liquidity resting on the Continuous Book
    • NS is returned identifying a self-matched trade in the IPO Auction
    • CSL is returned identifying a self-matched trade in the Closing Auction involving displayed liquidity resting on the Continuous Book
    • H is returned identifying a trade during a reopening process (i.e., a Halt Auction after a regulatory halt or Market-Wide Circuit Breaker Level 1 or Level 2 breach or a Volatility Auction after an LULD pause)

Note: 'L' will be provided in conjunction with a single-price cross execution when displayed orders on the Continuous Book are executed as part of the match. This behavior only applies to the Opening Match, Opening Auction, and Closing Auction; during a trading halt or pause, the Exchange does not consider orders to be displayed on the Continuous Book.

Which Tape will IEX-listed securities print and quote on?

IEX-listed securities will be Network B eligible securities (i.e., Tape B). Therefore, trade and quote information will be published on CTS Network B lines and CQS Network F lines, respectively, in a similar fashion to Bats-listed and NYSE American-listed securities.

How will my firm be notified when an IEX-listed security is subject to a short sale price test restriction under Rule 201 Regulation SHO?

If a short sale price test restriction is triggered for an IEX-listed security, firms that consume the real-time data feeds of the Exchange (DEEP v1.0 or TOPS v1.6) will receive a Short Sale Price Test Status Message with a Short Sale Price Test Status of '1.'

TOPS v1.5 will not identify when an IEX-listed security is subject to a short sale price test restriction. Firms consuming IEX data via TOPS v1.5 are encouraged to upgrade to TOPS v1.6 or DEEP v1.0 to receive greater visibility into the short sale restriction status of securities on IEX.

Firms may also consume short sale restriction status information from the CTA's CQS and CTS data feeds.

How will my firm be notified when an IEX-listed security is halted for regulatory reasons?

If an IEX-listed security is halted for regulatory reasons, firms that consume the real-time data feeds of the Exchange (DEEP v1.0 or TOPS v1.6) will receive a Trading Status Message with a Trading Status of 'H' signifying that trading in the subject IEX-listed security is halted across all US equity markets. Firms will receive a Trading Status Message with a Trading Status of 'O' signifying that the subject IEX-listed security has been released into an Order Acceptance Period. At the conclusion of a five-minute Order Acceptance Period, the Exchange will conduct a Halt Auction. Continuous trading will resume after the auction.

TOPS v1.5 will simply identify via the Quote Update Message Flags that the symbol is halted for trading. Firms consuming IEX data via TOPS v1.5 are encouraged to upgrade to TOPS v1.6 or DEEP v1.0 to receive greater visibility into the trading status of securities on IEX.

Firms may also consume trading halt information from the CTA's CQS and CTS data feeds. Via the CTS, Halt Reason will be specified as 'P' (New Pending) when the halt is first disseminated, then 'D' (New Dissemination) when the Order Acceptance Period has started.

How will my firm be notified when an IEX-listed security subject to a Limit Up-Limit Down trading pause?

Firms that consume the real-time data feeds of the Exchange (DEEP v1.0 or TOPS v1.6) will receive a Trading Status Message with a Trading Status of 'P' signifying that trading in the subject IEX-listed security is paused and the Order Acceptance Period has begun on IEX. IEX will invite orders for five minutes before conducting a Volatility Auction according to the LULD Amendment 12 specifications. Continuous trading will resume after the auction.

TOPS v1.5 will simply identify via the Quote Update Message Flags that the symbol is halted for trading. Firms consuming IEX data via TOPS v1.5 are encouraged to upgrade to TOPS v1.6 or DEEP v1.0 to receive greater visibility into the trading status of securities on IEX.

Firms may also consume trading pause information from the CTA's CQS and CTS data feeds. Via the CTS, Halt Reason will be specified as 'M' (LULD Trading Pause).

How will my firm be notified when an IEX-listed security is halted on IEX for operational reasons?

If an IEX-listed security is halted on IEX for operational reasons (e.g., due to a system disruption), firms that consume the real-time data feeds of the Exchange (DEEP v1.0 or TOPS v1.6) will receive an Operational Halt Status Message with an Operational Halt Status of 'O.' During an operational halt, other trading venues may freely trade IEX-listed securities. Continuous trading will resume without auction; IEX will simply publish an Operational Halt Status of 'N' signifying that trading in the subject IEX-listed security is not operationally halted on IEX.

TOPS v1.5 will simply identify via the Quote Update Message Flags that the symbol is halted for trading. Firms consuming IEX data via TOPS v1.5 are encouraged to upgrade to TOPS v1.6 or DEEP v1.0 to receive greater visibility into the trading status of securities on IEX.

Firms may also consume operational halt information from the CTA's CQS and CTS data feeds. Via the CTS, Halt Reason will be specified as 'X' (Equipment Changeover).

Official Price Calculations

How does the Opening (Closing) Auction affect the IEX Official Opening (Closing) Price?

The Opening Auction sets the IEX Official Opening Price. If an issue does not have an Opening Auction, the IEX Official Opening Price is determined by the first regular way last-sale eligible trade reported by IEX at or after 9:30 a.m., when regular trading hours begin.

The Closing Auction sets the IEX Official Closing Price. If a stock does not have a Closing Auction, the last regular way last-sale eligible trade reported by IEX prior to 4:00 p.m. is used as the IEX Official Closing Price.

How can a participant determine the official closing price of an IEX-listed security?

DEEP

For IEX-listed securities, the IEX Official Closing Price exists as of the completion of the closing process (i.e., receipt of a Security Event Message for the security indicating that the closing process is complete). The IEX Official Closing Price is the price of the last trade received for the security with the Extended Hours Flag OFF that has either the Single-price Cross Trade Flag ON or the Odd Lot Flag OFF. If no such trade exists, the IEX Official Closing Price is the previous official closing price, adjusted for corporate actions (if any) (i.e., equal to the Adjusted POC Price from the Security Directory Message for the subject security).

If a disruption occurs that prevents the execution of the Closing or Volatility Auction, as applicable, the IEX Official Closing Price will be the price of the final last sale eligible trade printed to the Consolidated Tape. IEX will not disseminate such price on DEEP, but it will be disseminated via the Consolidated Tape (i.e., CTS data feed).

TOPS

For IEX-listed securities, the IEX Official Closing Price exists as of the completion of the closing process (i.e., receipt of the first Quote Update Message for the security with the Market Session Flag ON after such message with the flag OFF). The IEX Official Closing Price is the price of the last trade received for the security with the Extended Hours Flag OFF that has either the Single-price Cross Trade Flag ON or the Odd Lot Flag OFF. If no such trade exists, the IEX Official Closing Price is the previous official closing price, adjusted for corporate actions (if any) (i.e., equal to the Adjusted POC Price from the Security Directory Message for the subject security).

If a disruption occurs that prevents the execution of the Closing or Volatility Auction, as applicable, the IEX Official Closing Price will be the price of the final last sale eligible trade printed to the Consolidated Tape. IEX will not disseminate such price on TOPS, but it will be disseminated via the Consolidated Tape.

Consolidated Tape

Upon completion of the Closing Auction (or the Volatility Auction for IEX-listed securities where an LULD trading pause exists at or after the Closing Auction Lock-in Time and before the Closing Auction), the IEX Official Closing Price for the security will be disseminated to the Consolidated Tape along with a bulk execution. The IEX Official Closing Price will be the price of the auction.

The IEX Official Closing Price will be represented by a sale condition code of 'M' (Market Center Official Close) in Category 4. The bulk execution will be represented by a sale condition code of '6' (Market Center Closing Trade) in Category 2 and a sale condition code of 'X' (Cross Trade) in Category 4. If the auction match results in an odd lot execution, the bulk execution will be represented by a sale condition code of '6' (Market Center Closing Trade) in Category 2 and a sale condition code of 'I' (Odd Lot Trade) in Category 4.

If a security does not have a Closing Auction, the IEX Official Closing Price will be the price of the Final Last Sale Eligible Trade and will be represented by a sale condition code of 'M' (Market Center Official Close) in Category 4.

How can a participant determine the official opening price of an IEX-listed security?

DEEP

For IEX-listed securities, the IEX Official Opening Price is the price of the first trade received on a trading day for the subject security with the Extended Hours Flag OFF that has either the Single-price Cross Trade Flag ON or the Odd Lot Flag OFF. For the IPO of an IEX-listed security, the IEX Official IPO Opening Price will be determined using the same methodology. If no such trade exists as of the completion of the closing process (i.e., receipt of a Security Event Message for the security indicating that the closing process is complete), the IEX Official Opening Price is the previous official closing price, adjusted for corporate actions (if any) (i.e., equal to the Adjusted POC Price from the Security Directory Message for the subject security).

If a disruption occurs that prevents the execution of the Opening or Halt Auction, as applicable, the IEX Official Opening Price will be the price of the initial last sale eligible trade printed to the Consolidated Tape. IEX will not disseminate such price on DEEP, but it will be disseminated via the Consolidated Tape.

TOPS

For IEX-listed securities, the IEX Official Opening Price is the price of the first trade received on a trading day for the subject security with the Extended Hours Flag OFF that has either the Single-price Cross Trade Flag ON or the Odd Lot Flag OFF. For the IPO of an IEX-listed security, the IEX Official IPO Opening Price will be determined using the same methodology. If no such trade exists as of the completion of the closing process (i.e., receipt of the first Quote Update Message for the security with the Market Session Flag ON after such message with the flag OFF), the IEX Official Opening Price is the previous official closing price, adjusted for corporate actions (if any) (i.e., equal to the Adjusted POC Price from the Security Directory Message for the subject security).

If a disruption occurs that prevents the execution of the Opening or Halt Auction, as applicable, the IEX Official Opening Price will be the price of the initial last sale eligible trade printed to the Consolidated Tape. IEX will not disseminate such price on TOPS, but it will be disseminated via the Consolidated Tape.

Consolidated Tape

Upon completion of the Opening Auction (or the Halt Auction for IEX-listed securities that have not traded during the Regular Market Session on that trading day), the IEX Official Opening Price for the security will be disseminated to the Consolidated Tape along with a bulk execution. The IEX Official Opening Price will be the price of the auction.

The IEX Official Opening Price will be represented by a sale condition code of 'Q' (Market Center Official Open) in Category 4. The bulk execution will be represented by a sale condition code of 'O' (Market Center Opening Trade) in Category 2 and a sale condition code of 'X' (Cross Trade) in Category 4. If the auction match results in an odd lot execution, the bulk execution will be represented by a sale condition code of 'O' (Market Center Opening Trade) in Category 2 and a sale condition code of 'I' (Odd Lot Trade) in Category 4.

If a security does not have an Opening Auction (e.g., no crossing interest), the Regular Market Session begins by canceling all On-Open orders and transferring any queued orders eligible for the Regular Market Session to the Continuous Book; the IEX Official Opening Price will be the price of the Initial Last Sale Eligible Trade and will be represented by a sale condition code of 'Q' (Market Center Official Open) in Category 4. The execution will be represented by a sale condition code of 'O' (Market Center Opening Trade) in Category 2.

Testing

Where can my firm test the submission of On-Open and On-Close ahead of Listings Launch?

Firms may currently test the submission of On-Open and On-Close interest in the ITF. Firms may test the submission of On-Open and On-Close interest in the Production environment beginning September 15. In both environments, On-Open and On-Close interest may only be submitted for IEX-listed securities.

Where can my firm test the consumption of IEX Auction Information ahead of Listings Launch?

Firms may currently test the consumption of IEX Auction Information on DEEP v1.0 or TOPS v1.6 in the ITF. Firms may test the consumption of IEX Auction Information on DEEP v1.0 or TOPS v1.6 in the Production environment beginning September 15.

Firms may also receive portions of IEX Auction Information via the CTS binary feed once it is launched. In the binary feed, the CTA is introducing a new Auction Status message which will contain auction collar and extension information.

Are there test symbols that are listed on IEX?

To allow for future production testing of updates to the CQS and CTS data feeds, IEX has reserved the following test symbols as IEX-listed securities:

  • ZIEXT
  • ZEXIT
  • ZXIET

Market participants should be prepared to accept messages for the above test symbols on Network B production feeds by Friday, September 15. SIAC will provide four Saturday testing opportunities before launching the test symbols on the production feeds: August 12, August 19, August 26, and September 9.

Contingency Procedures

How will IEX notify firms of contingency actions for IEX-listed securities?

IEX will publicly announce at the earliest possible time the initiation of the contingency procedures via System Status and email notification directories.

What are the contingency plans around closing auctions for IEX-listed securities?

In the event of systemic issues, the determination to use the Closing Auction Primary or Secondary Contingency Procedures will be made by the President of IEX or any senior level employee designated by the President. IEX will employ the Closing Auction Primary Contingency Procedures if at all possible, and will employ the Closing Auction Secondary Contingency Procedures only if it determines that both the standard closing procedures and the Primary Contingency Procedures are unavailable.

Closing Auction Primary Contingency Procedures

IEX will publicly announce that no Closing Auction will occur. The price of the Final Consolidated Last Sale Eligible Trade will be used for the IEX Official Closing Price. The IEX Official Closing Price will be published to the Consolidated Tape. IEX will execute orders on the Auction Book at the IEX Official Closing Price. All remaining orders on the Order Book will be canceled at the conclusion of the contingency process. IEX will report the resulting execution to the Consolidated Tape and deliver execution reports to Users.

Closing Auction Secondary Contingency Procedures

If IEX publicly announces at or before 3:00 p.m. ET that it will employ the Secondary Contingency Procedures for one or more securities, it will designate a back-up exchange for those securities, cancel all open interest on the Order Book in order to give Users the opportunity to route their orders to alternative execution venues, and the IEX Official Closing Price for each security will be determined based on the following hierarchy:

  1. The IEX Official Closing Price will be the official closing price established for the security under the rules of the designated back-up exchange.
  2. If there is no official closing price in a security on the designated back-up exchange, the IEX Official Closing Price will be the volume weighted average price ("VWAP") of the last sale eligible trades reported to the Consolidated Tape during the last five minutes of Regular Market Hours on that trading day, including any closing transactions on an exchange and any trade breaks or corrections up to the time the VWAP is processed.
  3. If there are no last sale eligible trades reported to the Consolidated Tape during the last five minutes of Regular Market Hours, the IEX Official Closing Price of such security will be the Final Consolidated Last Sale Eligible Trade for the security on that trading day.
  4. If there were no last sale eligible trades reported to the Consolidated Tape on that trading day, the IEX Official Closing Price will be the previous official closing price.

If IEX publicly announces after 3:00 p.m. ET that it will employ the Secondary Contingency Procedures for one or more securities, it will cancel all open interest on the Order Book in the subject securities in order to give participants the opportunity to route their orders to alternative execution venues, and the IEX Official Closing Price for each security will be determined based on the following hierarchy:

  1. The IEX Official Closing Price will be the VWAP of the last sale eligible trades reported to the Consolidated Tape during the last five minutes of Regular Market Hours on that trading day, including any closing transactions on an exchange and any trade breaks or corrections up to the time the VWAP is processed.
  2. If there are no last sale eligible trades reported to the Consolidated Tape during the last five minutes of Regular Market Hours, the IEX Official Closing Price of such security will be the Final Consolidated Last Sale Eligible Trade for the security on that trading day.
  3. If there were no last sale eligible trades reported to the Consolidated Tape on that trading day, the IEX Official Closing Price will be the previous official closing price.

What are the contingency plans around opening auctions for IEX-listed securities?

IEX will publicly announce that no Opening Auction will occur. The price of the Initial Consolidated Last Sale Eligible Trade will be used for the IEX Official Opening Price. The IEX Official Opening Price will be published to the Consolidated Tape. All orders on the Order Book will be canceled, and the security will open for trading without an auction.

Security Details and Corporate Actions

Firms that consume the real-time data feeds of the Exchange (DEEP v1.0 or TOPS v1.6) will receive a Security Directory Message during the pre-market spin for each IEX-listed security. This message provides important trading related information such as round lot size, LULD tier, adjusted previous official closing price, test security flag, and When Issued flag.

Additionally, IEX will provide a list of all IEX-listed securities and their corresponding data fields, including symbology using a variety of formats, via a pipe separated file posted to the Exchange's public website free of charge. This document will be generated and posted to the IEX website at 8:30 p.m. ET before each trading day, then once per hour from 9 p.m. ET until 6 p.m. ET the following day.

Please review the IEX Daily List File Specification for more details on the IEX-Listed Symbol Directory Daily List.

How can my firm find the CUSIP for IEX-listed securities?

IEX will provide a list of all IEX-listed securities and their corresponding data fields, including CUSIP, via a pipe separated file posted to the Exchange's public website free of charge. This document will be generated and posted to the IEX website at 8:30 p.m. ET before each trading day, then once per hour from 9 p.m. ET until 6 p.m. ET the following day. Securities IEX anticipates to list, either because of a future IPO or transfer from another listing venue, will be identified in this list with the "First Date Listed" equal to "0" until IEX identifies an anticipated listing date.

Two versions of each file will be available: one with CUSIP data and one without. Only participants with a proper CUSIP license may download files containing CUSIP data. Participants who wish to access the CUSIP version of these files must provide their CUSIP license information when creating an account for the website. Access to download the CUSIP version will be granted only after IEX has verified licensing.

Please review the IEX Daily List File Specification for more details on the IEX-Listed Symbol Directory Daily List.

How will IEX notify firms of corporate actions for IEX-listed securities?

New issues, symbol and name changes, and deleted issues, as well as new firms, name changes, and deleted firms for IEX-listed securities will be provided via a pipe separated file posted to the Exchange's public website free of charge. The file will be generated and posted to the IEX website once per hour from 8:00 a.m. to 6:00 p.m. ET on each trading day.

Please review the IEX Daily List File Specification for more details on the IEX Corporate Actions Daily List.

How will IEX notify firms of dividend, stock split, and next day ex-date information for IEX-listed securities?

Details about upcoming dividend information and other corporate actions, such as stock splits, for IEX-listed securities, as well as advance notification of dividend declarations impacting IEX-listed securities will be provided via pipe separated files posted to the Exchange's public website free of charge. Files will be generated and posted to the IEX website once per hour from 8:00 a.m. to 6:00 p.m. ET on each trading day.

Please review the IEX Daily List File Specification for more details on the IEX Dividends Daily List and IEX Next Day Ex-Dates Daily List.

Exchange FAQ

How does my firm become a Member of IEX?

See the Becoming a Member section in our Exchange FAQ page.

How can my firm connect to IEX?

See the Getting Connected section in our Exchange FAQ page.

What Exchange data products are available and how can my firm receive them?

See the Receiving Exchange Data Products section in our Exchange FAQ page.

How is IEX identified on market data feeds and various other platforms?

See the Identifying the Exchange section in our Exchange FAQ page.