Self-Regulatory Organizations; Nasdaq PHLX LLC; Notice of Filing and Immediate Effectiveness of Proposed Rule Change To Amend Electronic FLEX Rules
Published Date: 2/2/2026
Notice
Summary
Nasdaq PHLX is upgrading its electronic FLEX trading rules to make trading easier and more flexible. Now, prices can be shown as percentages, a new Delta-Adjusted at Close order type is added, and traders can mix FLEX and non-FLEX options in complex orders. These changes take effect immediately and aim to help traders move faster and smarter without extra costs.
Analyzed Economic Effects
3 provisions identified: 3 benefits, 0 costs, 0 mixed.
Delta-Adjusted-at-Close (DAC) Orders
Nasdaq PHLX adds a Delta-Adjusted at Close (DAC) instruction that lets a FLEX order execute intraday and then be adjusted at the market close using the formula P2 = P1 + (U - R) * D, where D (delta) is designated by the Member and may be input to four decimals. DAC orders: may only be used for series with fixed-dollar exercise prices (not percentage-priced series), must designate a delta per leg for complex orders, simple single-stock DAC orders cannot be submitted earlier than 45 minutes before market close, and may not be submitted on expiration day.
FLEX Prices Can Be Percentages
Nasdaq PHLX now allows FLEX option prices (exercise prices, bids/offers, and minimum increments) to be expressed as a percentage of the underlying's closing value on the trade date, with a minimum percentage increment of 0.01%. After applying the percentage to the closing value the System rounds the resulting dollar price to the nearest fixed minimum increment (for example, $0.01).
Mix FLEX and Non-FLEX Legs Allowed
The Exchange will permit legs of a complex FLEX Order to include a combination of FLEX Option series and non-FLEX Option series (a "FLEX v. Non-FLEX Order"), allowing traders to submit multi-leg complex orders that mix FLEX and non-FLEX legs in a single order. The change aligns Phlx rules with an analogous capability used by another exchange.
Your PRIA Score
Personalized for You
How does this regulation affect your finances?
Sign up for a PRIA Policy Scan to see your personalized alignment score for this federal register document and every other regulation we track. We analyze your financial profile against policy provisions to show you exactly what matters to your wallet.
Key Dates
Department and Agencies
Take It Personal
Get Your Personalized Policy View
Start a Free Government Policy Watch to see how policy affects your household, then upgrade to PRIA Full Coverage for year-round monitoring.
Already have an account? Sign in