Average Midpoint is a current Regulation NMS defined term. This guide preserves the share weighting and timing rules instead of reducing it to an ordinary arithmetic midpoint.
ReviewedEvidence1 sourceSectionPhrases & Idioms
Quick answer
Under Regulation NMS, average midpoint is the share-weighted average of the midpoint of the national best bid and offer at the rule-specified time for the relevant orders.
Key details
Canonical FormAverage Midpoint
Core MeaningThe share-weighted average of the midpoint of the national best bid and national best offer at order receipt or, for specified order types, when the order first becomes executable.
Further guidance
History Boundary
This page reflects the current reviewed 17 CFR § 242.600 definition and should be rechecked if Regulation NMS changes.
Meaning
17 CFR § 242.600 defines average midpoint with share weighting and order-type timing rules.
Usage Boundary
Do not replace the rule-defined timing with a generic midpoint calculation.
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
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Average Percentage Effective Spread is a current Regulation NMS defined metric and should be read with the rule-defined average effective spread and average midpoint components.
Average Percentage Realized Spread is a current Regulation NMS defined metric; the page keeps its rule-defined denominator and does not substitute a generic percentage-spread meaning.
Average Quoted Spread is a current Regulation NMS defined term. This guide preserves share weighting and the special executable-time rule for midpoint-or-better limit-order executions.
Average Realized Spread is a current Regulation NMS defined term. This guide preserves its share weighting, buy/sell direction, post-execution timing, and final-trading-hours midpoint provision.
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Actionable Indication of Interest is a current federal securities-regulation defined term. This guide preserves the rule-specific definition and boundaries instead of replacing it with informal market shorthand.
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