In light of the adoption of SEC Rule 600(b)(93), a new tiered round lot structure will come into effect starting November 3, 2025. Pursuant to Rule 600(b)(93), round lots will be assigned semiannually and will be based on a stock's average closing price during the designated evaluation period. NSCC understands that for any National Market System (NMS) stock, round lots will be determined based on the average closing price on the primary listing exchange during the prior evaluation period in accordance with the following tiers: • $250.00 or less per share, an order for the purchase or sale of an NMS stock of 100 shares • $250.01 to $1,000.00 per share, an order for the purchase or sale of an NMS stock of 40 shares • $1,000.01 to $10,000.00 per share, an order for the purchase or sale of an NMS stock of 10 shares • $10,000.01 or more per share, an order for the purchase or sale of an NMS stock of 1 share NSCC currently publishes round lot size in the “Unit of Trading” field in CNS EQUITY MASTER FILE, AUTOROUTE ID: 02040290 daily report based on information provided by the exchanges. Starting November 3, 2025, this value will no longer be populated in this daily report.
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