The Financial Industry Regulatory Authority (Finra) has joined the chorus of outcries over trading halts in GameStop shares with a notice that reminds broker-dealers what their best execution and order flow obligations are during times of extreme stock market volatility.

The notice comes on the heels of Robinhood’s now infamous trading halts of speculative trading in GameStop (GME), which sent the stock price soaring in late January.

“While Finra recognizes the challenges that member firms may face during extreme market volatility, particularly when conditions change quickly, firms nevertheless should be prepared to provide customers ongoing access to the securities markets. To this end, firms must be prepared to handle customer orders fairly, consistently, and reasonably at all times,” the self-regulatory agency said.

However, broker-dealers “are not obligated to receive or accept orders from customers where the firms believe that the associated compliance or legal risks are unacceptable, and there may be situations where firms determine they must change their order handling procedures to restrict the entry or acceptance of customer orders to limit the firm’s exposure to extraordinary market risk,” Finra said.

A firm’s policy changes to best execution must be made “on fair, consistent and reasonable terms," Finra said, adding that in circumstances where customers submit marketable customer orders, broker-dealers are “obligated” to handle such orders promptly.

The activation of procedures designed to respond to extreme market conditions “may be implemented only when warranted by market conditions and that member firms should document the basis for activating any modified procedures,” Finra said.

If a broker-dealer frequently activates their modified order handling procedures because they’ve “failed to maintain adequate system capacity to handle exceptional loads” it may raise best execution concerns with regulators, Finra warned.

Finra said that if firms perform appropriate planning and testing, it will help them avoid or mitigate the need to implement procedure changes in the first place.

Finra also reminded firms that to avoid excessive or unwarranted activation of modified order handling procedures, they need to take steps to prevent their operational systems from being overwhelmed by periodic spikes in systems message traffic due to high volume.

Broker-dealers should also “be prepared to adjust margin requirements during periods of extreme price volatility and take a proactive approach to meeting their obligations for strong funding and liquidity management practices during adverse periods,” Finra said.

Finra also said that broker-dealers should deliver “meaningful” customer disclosures about how their best execution and order fulfillment procedures may change during extreme market events.

“Appropriate meaningful disclosures may help inform whether a firm acted fairly, consistently and reasonably. Importantly, however, Finra has emphasized that a firm cannot rely on disclosures alone to justify deficient order handling procedures,” Finra said.

However, disclosures of alternative order handling procedures that are “unfair or otherwise inconsistent with a member firm’s best execution obligations would neither correct the deficiencies with such procedures nor absolve the firm of potential best execution violations,” Finra said.

Disclosures in customer account agreements that state a firm may, in its sole discretion, prohibit or restrict trading without notice, do not relieve a firm of its obligation to handle orders in a manner that is fair, consistent and reasonable, Finra said.

Firms should also consider disclosing to investors that stop prices are not guaranteed execution prices. “The price at which a stop order ultimately is executed may be very different from the investor’s stop price. Accordingly, while a customer may receive a prompt execution of a stop order that becomes a market order, during volatile market conditions, the execution may be at a significantly different price from the stop price if the market is moving rapidly,” Finra said.