Session volume-weighted average for limit placement and listed routing

The session average as a transfer yardstick

Volume-weighted average price is the sum of each print's price times its size, divided by total shares traded. That share-weighted average of the session's prints is used as a standardized same-day transfer price rather than a directional forecast.

Brokers and customers use the session volume-weighted average as a standardized same-day price at which to transfer stock to each other. If the last price is 30 while that session average is 30.20, the stock is trading below the volume-weighted average.

Limits that rest, step through, or miss

A limit order is a priced instruction that can rest, improve, or miss. On specialist turnaround, a limit entered a penny or two through the posted bid or offer can still fill at the displayed price or better. Stepping a tick through the displayed quote can still print at the posted price when the venue matches at the best standing limit.

One described practice is to cancel about 80% of placed orders so size does not rest after an immediate opportunity is missed.

Routing that pays or improves the spread

Order routing is the choice between specialist turnaround and an electronic book. That choice changes fill speed, quote reliability, and whether the spread is paid or improved. Specialist turnaround is listed routing in which an assistant can match incoming limits at the best posted price, sometimes with improvement versus the price the trader typed.

An electronic communications network is a book that either fills immediately or posts the residual as a bid or offer. Taking the bid or lifting the offer surrenders the spread, which is the usual result when liquidity is taken on an electronic book. A listed quote can remain displayed after a buy-at-the-ask or sell-at-the-bid attempt goes unfilled.

A specialist post may oversee a couple of dozen names but only two or three that trade heavily, so inactive names often show wider spreads and outside live orders. Trade-through protection is a listed rule that can force a large order to receive a better standing price, creating an accommodation print for liquidity already on that side of the book.