FINRA Rule 6100

Its FINRA. page returns only the title — 6100. QUOTING AND TRADING IN NMS STOCKS — with no rule text, no amendment history, and no selected notices. It serves exclusively as the organizational container for its child rules.

FINRA Rule 6100 sits within the 6000 Quotation, Order, and Transaction Reporting Facilities series, immediately following FINRA Rule 6000's top-level series marker and immediately preceding FINRA Rule 6110, the first substantive child rule of the sub-series.

What NMS Stocks Are

An NMS stock — or National Market System stock — is any equity security other than an option for which transaction reports are collected, processed, and made available pursuant to an effective transaction reporting plan under SEC Regulation NMS. In practical terms, NMS stocks are the universe of U.S.-listed equity securities, including stocks listed on the New York Stock Exchange, the Nasdaq Stock Market, NYSE American, and other registered national securities exchanges. The NMS designation subjects these securities to the full regulatory framework of SEC Regulation NMS — including the Order Protection Rule (preventing trade-throughs of protected quotations), the Access Rule (ensuring fair access to quotations), the Sub-Penny Rule (restricting quotation increments for stocks priced at or above $1.00), and the Market Data Rules governing consolidated tape dissemination.

The Scope of FINRA Rule 6100's Sub-Series

FINRA Rule 6100's sub-series addresses the off-exchange dimension of NMS stock trading — member firm activity in NMS stocks that occurs outside national securities exchange matching engines, commonly referred to as over-the-counter trading in exchange-listed securities. Off-exchange trading in NMS stocks has grown substantially as a proportion of total U.S. equity trading volume over the past two decades, driven by the proliferation of alternative trading systems (ATSs), dark pools, and broker internalization programs that route and execute customer orders away from exchange venues.

The complete child rule list confirmed from the FINRA.org 6000 series page is: FINRA Rule 6110 (Trading Otherwise than on an Exchange), FINRA Rule 6120 (Trading Halts), FINRA Rule 6121 (Trading Halts Due to Extraordinary Market Volatility), FINRA Rule 6130 (Transactions Related to Initial Public Offerings), FINRA Rule 6140 (Other Trading Practices), FINRA Rule 6150 (Obligation to Provide Information), FINRA Rule 6151 (Disclosure of Order Routing Information for NMS Securities), FINRA Rule 6160 (Multiple MPIDs for Trade Reporting Facility Participants), FINRA Rule 6170 (Multiple MPIDs for Alternative Display Facility Participants), FINRA Rule 6180 (Transaction Reporting — itself a sub-marker), FINRA Rule 6181 (Timely Transaction Reporting), FINRA Rule 6182 (Trade Reporting of Short Sales), FINRA Rule 6183 (Exemption from Trade Reporting Obligation for Certain Alternative Trading Systems), FINRA Rule 6184 (Transactions in Exchange-Traded Managed Fund Shares), FINRA Rule 6190 (Compliance with Regulation NMS Plan to Address Extraordinary Market Volatility), and FINRA Rule 6191 (Compliance with Regulation NMS Plan to Implement a Tick Size Pilot Program).

The Sub-Series' Three Functional Clusters

FINRA Rule 6100's child rules address three distinct functional areas.

The first cluster — trading practices and restrictions — governs the behavioral standards for member firms engaging in off-exchange NMS stock activity. FINRA Rule 6110 defines what it means to trade otherwise than on an exchange and establishes FINRA's trading transparency publication obligations. FINRA Rules 6120 and 6121 govern when FINRA must halt off-exchange trading — Rule 6120 addressing general trading halts including Regulatory Halts declared by primary listing exchanges, and Rule 6121 addressing the specific Limit Up-Limit Down (LULD) Plan-based trading pauses for extraordinary market volatility. FINRA Rule 6130 restricts off-exchange trading in IPO securities before the primary listing exchange opens the security for trading. FINRA Rule 6140 establishes other trading practice standards including the bona fide quotation requirement and passive market making restrictions.

The second cluster — information and quotation obligations — addresses the transparency and market participant identifier requirements applicable to off-exchange NMS stock market participants. FINRA Rule 6150 governs members' obligations to provide information to FINRA about their trading activities. FINRA Rule 6151 addresses disclosure of order routing information under SEC Rule 606 of Regulation NMS. FINRA Rules 6160 and 6170 govern members' use of multiple Market Participant Identifiers (MPIDs) — the unique identifiers through which members identify themselves in trade reports and quotations submitted to FINRA's TRFs and ADF respectively.

The third cluster — transaction reporting — governs the post-trade transparency obligations applicable to off-exchange NMS stock transactions. FINRA Rule 6180 serves as a sub-marker organizing the transaction reporting rules. FINRA Rule 6181 establishes the 10-second timely transaction reporting requirement. FINRA Rule 6182 requires short sale designation in trade reports. FINRA Rule 6183 provides an exemption from transaction reporting obligations for certain alternative trading systems. FINRA Rule 6184 addresses specific reporting requirements for transactions in exchange-traded managed fund shares. And FINRA Rules 6190 and 6191 address compliance with the LULD Plan and the Tick Size Pilot Program respectively.

FINRA Rule 6100 and SEC Regulation NMS

SEC Regulation NMS — adopted in 2005 and fully effective in 2007 — fundamentally restructured U.S. equity market regulation by establishing a unified regulatory framework applicable across all trading venues for NMS stocks. FINRA Rule 6100's sub-series represents FINRA's implementation of Regulation NMS-consistent standards for the off-exchange dimension of NMS stock trading — ensuring that off-exchange trading operates under regulatory standards that are consistent with, and in many cases directly incorporate, the Regulation NMS requirements applicable to exchange trading.

The most direct Regulation NMS connection within FINRA Rule 6100's sub-series is through FINRA Rule 6190's compliance obligation — requiring FINRA to enforce the LULD Plan's price band and trading pause requirements on its ADF and TRF facilities, mirroring the identical obligation that Regulation NMS imposes on national securities exchanges. This parallel compliance structure ensures that LULD Plan protections apply uniformly across all trading venues, exchange and off-exchange alike, preventing market participants from circumventing trading pauses or price band limitations by routing trades to off-exchange venues during periods when exchange trading is restricted.

The Relationship Between FINRA Rule 6100 and FINRA Rules 6200, 6300, 6400, 6600, and 6700

FINRA Rule 6100's Quoting and Trading in NMS Stocks sub-series addresses the trading practice, information, and transaction reporting dimensions of off-exchange NMS stock activity — but does not itself establish the specific facilities through which that activity is reported. Those facilities are addressed in the parallel sub-series within FINRA Rule 6000: FINRA Rule 6200 (Alternative Display Facility, providing both quotation display and trade reporting for NMS stocks), FINRA Rule 6300 (Trade Reporting Facilities, providing transaction-only reporting for off-exchange NMS stock trades through the FINRA/Nasdaq TRF and FINRA/NYSE TRF), FINRA Rule 6400 (addressing the parallel framework for OTC equity securities rather than NMS stocks), FINRA Rule 6600 (OTC Reporting Facility for OTC equity transactions), and FINRA Rule 6700 (TRACE for fixed income securities).

This organizational structure — FINRA Rule 6100 governing what must be done (trading practices, information obligations, transaction reporting) while FINRA Rules 6200 and 6300 govern the specific facilities through which transaction reporting is accomplished — reflects FINRA's separation of substantive trading standards from the operational mechanics of the specific reporting facilities.

Connection to FINRA Rules 5310, 6000, 6110, 6120, 6121, 6130, 6140, 6180, 6181, 6182, 6190, 6200, 6300, and SEC Regulation NMS

FINRA Rule 6100 connects to FINRA Rule 6000 as its parent series marker. It connects to FINRA Rule 5310 — whose best execution obligations require members to seek the most favorable terms reasonably available for customer orders in NMS stocks, with FINRA Rule 6100's transparency and reporting framework providing the price information infrastructure through which best execution compliance can be assessed. It connects to SEC Regulation NMS — whose Order Protection Rule, Access Rule, Sub-Penny Rule, and Market Data Rules provide the federal regulatory backdrop within which FINRA Rule 6100's child rules operate. And it connects to each of its confirmed child rules — FINRA Rules 6110 through 6191 — as the operative provisions whose collective content gives FINRA Rule 6100's Quoting and Trading in NMS Stocks sub-series its substantive meaning.

Examination Relevance and Key Takeaways

FINRA Rule 6100 is tested on the Series 7 and Series 24 examinations as the organizational framework for off-exchange NMS stock trading — providing the context for understanding how the specific trading practice, information, and transaction reporting rules in the 6110 through 6191 series relate to each other and to the broader market structure.

The key points to retain are these: FINRA Rule 6100 has no operative text — it organizes the Quoting and Trading in NMS Stocks sub-series; NMS stocks are exchange-listed equity securities subject to SEC Regulation NMS; the sub-series addresses three functional clusters — trading practices and restrictions (FINRA Rules 6110 through 6140), information and quotation obligations (FINRA Rules 6150 through 6170), and transaction reporting (FINRA Rules 6180 through 6191); the sub-series governs the off-exchange dimension of NMS stock trading — member firm activity occurring outside national securities exchange matching engines through ATSs, dark pools, and broker internalization; and FINRA Rule 6100's child rules implement Regulation NMS-consistent standards for off-exchange trading, with FINRA Rule 6190's LULD Plan compliance obligation ensuring parallel application of extraordinary market volatility protections across all trading venues.