Max Quantity Per Ticker

This message indicates that TradersPost blocked the order because filling it would take you past the maximum you set for that ticker — either the row is set to Reject order, or it is set to Reduce to max but the order could not be trimmed (for example a dollar-amount order, a multi-leg plan, or no room left under the maximum). Set those maximums under Ticker Quantity Limits on the broker account, separately for live and paper. Enter underlyings, futures roots, and crypto pairs — for example SPY, NQ, or BTC-USD — not individual option or futures contracts, and not a bare crypto base like BTC. Use Applies to when you want different maximums for shares vs option contracts on the same underlying.

The maximum applies to the underlying, so everything you hold on SPY counts toward the SPY limit, whatever the expiration or strike, and every NQ contract month counts toward NQ. Long and short both count rather than cancelling out, and shares are counted separately from contracts. When a row says Reduce to max, quantity-based single-leg orders are trimmed to fit instead of blocked, and the trade shows Max Quantity Per Ticker Reduced; an order that reduces what you hold is allowed even when you already hold more than the maximum.

For example, with a SPY maximum of 100 and 80 already open, an order for 50 is rejected under Reject order (this message) and reduced to 20 under Reduce to max. Resting broker orders are not counted — only current holdings, the order being placed, and any other legs of the same trade plan.

Reducing stops at zero: an order large enough to close what you hold and open a position on the other side is measured on that new position. With 120 held long against a maximum of 100, a sell of 230 is rejected under Reject order because it would leave you short 110, even though it leaves you holding less than you started with.