Uptick Rule: The 10% Trigger Under SEC Rule 201

How traders can check a Rule 201 restriction

First confirm that the security is covered by Regulation SHO and identify the prior day's closing price from the relevant listing market. Calculate the 10% threshold from that official reference rather than from an after-hours print or an intraday high. Then check the exchange, broker, or market-data indicator showing whether the circuit breaker has been triggered. A large decline on a chart is not by itself proof that every short-sale order is currently restricted.

When the restriction is active, a short-sale order generally cannot be executed or displayed at a price less than or equal to the current national best bid, subject to the rule's exceptions. The national best bid can move after the order is submitted, so an order accepted by a broker may be repriced, held, or remain unfilled. A long holder selling owned shares is not placing the same type of short-sale order, although account marking and delivery rules still matter.

Record the trigger date because the restriction continues for the remainder of that day and the following trading day. Holidays and weekends do not create extra trading days. If a platform rejects an order, request the rejection code and ask whether the cause was Rule 201, locate availability, buying power, broker policy, or another control. Similar symptoms can have different causes.

Backtesting the alternative uptick rule

A historical test needs more than daily closing prices. To identify the trigger accurately, it needs the prior official close and intraday trades showing when the 10% decline first occurred. To model permitted executions, it also needs contemporaneous national best bid data and short-sale order markings. A daily bar can show that the day's low crossed the threshold but cannot reconstruct which later orders were executable.

Avoid treating the restriction as a directional signal. Rule 201 changes how certain short sales may be displayed or executed; it does not guarantee a rebound or prevent further price declines. Compare restricted and unrestricted observations with controls for volatility, news, liquidity, and market conditions before interpreting any performance difference.

For current trading, rely on the broker's live controls and official regulatory sources. For research, document the data vendor, timestamps, corporate-action adjustments, and rule version used so another analyst can reproduce the classification.

Distinguishing Rule 201 from broker controls

A rejected short sale can result from several independent controls: the security may be hard to borrow, the broker may lack a locate, the account may lack margin, or the firm may impose a house restriction. Rule 201 addresses the price test after its trigger; it does not replace these other requirements. Ask for the specific rejection reason before changing the order.

Broker interfaces can mark an order “short,” “short exempt,” or “sell” based on the account position and order details. Customers should not select an exempt marking unless the broker's process and the applicable exception support it. Accurate order marking and locate compliance remain important even when the price test is not active.

Frequently asked questions

What triggers the alternative uptick rule?

A decline of 10% or more from the security’s prior-day closing price.

How long does the restriction last?

For the remainder of the day when triggered and the next trading day.

Does Rule 201 prevent an investor from closing a long position?

No. It concerns covered short sales, not an ordinary sale of shares already owned. Accurate order marking remains important.

Are there exceptions?

Yes. Rule 201 includes defined exceptions and operational provisions. Consult the official rule for a specific compliance question.

Sources and Further Verification

• SEC Release No. 34-61595: Amendments to Regulation SHO
• SEC: Fast Answers—Short Sale Price Test Restrictions