What Best Execution In Equity Trading Really Means - Part 1

Arthur Levitt, Chairman emeritus of the SEC, said atinstitutional investors and large orders. Considering
an SIA conference in Boca Raton in November 1999:that large orders are often worked over multiple
Best execution encompasses a number of factorsdays, and the value of the definition dwindles.
starting with the price of the execution and theAdditionally, consider market volatility in context with
opportunity for price improvement. Other factorsdaily VWAP (volume weighted average price, a price
include speed and likelihood of execution. Forpoint few institutional traders want to exceed in
institutional investors, anonymity and liquidity might betrading); today's worst price can be much better than
overriding concerns. In any case, the quality oftomorrow's best price. Therefore, the definition
execution must always be viewed from thementioned earlier lacks validity in today's environment.
customer's perspective, not the firm's.Due to the sheer number of variables present in any
This paper discusses the concept of best executionmarket it is difficult, if not impossible, to show that
in that light, the regulatory environment in which it isthe best possible execution is actually achieved. Many
defined, and examines a number of approaches forfirms quote best execution as a marketing tool to sell
the investor to obtain the best execution possible.their products and services; however no firm will
Best Executionguarantee that best execution is ever achieved.
Best execution means different things to differentThe number of firms who advertise best execution
people. To some it means attaining the inside price ofhas grown significantly over the past few years,
the best quoted bid or offer for an order. To others,primarily as the number of participants within the
notably institutional investors or traders, it meanscapital markets arena has grown. As trading volume
working a large order without moving the market inhas increased so has the number of execution
an adverse manner.venues (in conjunction with a loosening of financial
Traditionally, one would assume that achieving theregulations). The increase in competition and number
best execution is the same as finding the best priceof execution venues has lead to increasingly
for a trade at the time the trade needs to be made.fragmented pools of liquidity and the necessity for
This seems reasonable at first glance, but upon closerdevelopment of algorithms to discern ways of
inspection, one might find that the time horizonachieving optimal execution within this environment.
considered here is too short, particularly for