Front-Running Explained

By Samuel Becker · September 29, 2023 · 7 minute read

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Front-Running Explained

Front running is when a broker trades a financial asset on the basis of non-public information that will influence the price of the asset in order to profit. In most cases front running is illegal because the broker is acting on information not available to the public markets, for their own gain.

Front running is somewhat different from insider trading, where an individual investor working at a company is able to place a trade based on proprietary information about that company. Insider trading is also illegal.

There is another definition of front running, however, that involves index funds. This type of front running is not illegal.

What Is Front Running?

In short, front running trading means that an investor buys or sells a security (a stock, bond, etc.) based on advance, non-public knowledge or information that they believe will affect its stock price. Because the information is not widely available, it gives the trader or investor an advantage over other traders and the market at large.

Based on this definition of front running, it’s easy to see how the practice — though illegal — earned its moniker. Traders, making moves based on privately held information, are getting out ahead of a price movement — they’re running out in front of the price change, in a very literal sense.

In addition to stocks, front running may also involve derivatives, such as options or futures.

Again, although front running is technically different from insider trading, the two are quite similar in practice, and both are illegal. Front running is forbidden by the SEC. It also runs afoul of the rules set forth by regulatory groups like the Financial Industry Regulatory Authority (FINRA).

Recommended: Everything You Need to Know About Insider Trading

If a trader has inside knowledge about a particular stock, and makes trades or changes their position based on that knowledge in order to profit based on their expectations derived from that knowledge, that’s generally considered a way of cheating the markets.

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How Front Running Works

The definition of front running and how it works is pretty straightforward, and there are two main ways front running — also called tailgating — can occur.

•   A broker or trader gets wind of a large upcoming trade from one of their institutional clients, and the size of the trade is sure to influence the price.

•   Or the broker learns of a specific analyst report about a given security that’s likely going to impact the price.

In either case, the trader gains access to price-relevant information that’s not yet available to the public markets, and the broker is well aware that the upcoming trade will substantially impact the price of the asset. So before they place the trade, they might either buy, sell, or short the asset — depending on the nature of the information at hand — and make a profit as a result.

A Front Running Example

Let’s run through a hypothetical example of how one form of front running may work.

Say there’s a day trader working for a brokerage firm, and they manage a number of client’s portfolios. One of the broker’s clients calls up and asks them to sell 200,000 shares of Company A. The broker knows that this is a big order — big enough to affect Company A’s stock price immediately.

With the knowledge that the upcoming trade will likely cause the stock price to fall, the broker decides to sell some of his own shares of Company A before he places his client’s trade.

The broker makes the sale, then executes the client’s order (blurring the lines of the traditional payment for order flow). Company A’s stock price falls — and the broker has essentially avoided taking a loss in his own portfolio.

He may use the profit to invest in other assets, or buy the newly discounted shares of Company A, potentially increasing his long-term profits essentially by averaging down stocks.

The trader would’ve broken the law in this scenario, breached his fiduciary duties to his client, and also acted unethically.

Recommended: Understanding the Risks of Day Trading

Front Running in the Real World

There are many real-world examples of front running that have led to securities fraud, wire fraud, or other charges. Back in 2009, for instance, 14 Wall Street firms were hit with roughly $70 million in fines by the SEC for front running.

“The SEC charged the specialist firms for violating their fundamental obligation to serve public customer orders over their own proprietary interests by ‘trading ahead’ of customer orders, or ‘interpositioning’ the firms’ proprietary accounts between customer orders,” an SEC release read.

Further research into the topic of front running finds that when people (or firms) have insider knowledge that could benefit them in the markets, they’re likely to use it.

As for another real-world example of front running, there was a case in 2011 involving a large global bank, and some foreign exchange traders who found themselves in hot water. The two traders became privy to a pending order from a client, made some moves to get ahead of it, and ended up making their company money.

It was a $3.5 billion transaction, and by front running the trade, the traders were able to make more than $7 million. It’s not a happy ending, however, the people involved ended up sentenced to prison and ordered to pay hundreds of thousands of dollars in fines.

So, while front running does happen, there can be serious consequences if regulators catch wind of it.

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Is Front Running Legal?

No. In almost all cases, front running is illegal.

Are There Times When Front Running Is OK?

Yes, actually. Index front running is not illegal, and is actually fairly common among active investors.

As many investors are aware, index funds track market indexes like the S&P 500 or Dow Jones Industrial Average. These funds are designed to mirror the performance of a market index. And since market indexes are really nothing more than big amalgamations of stocks, they change quite often. Companies are frequently swapped in and out of the S&P 500 index, for instance.

When that happens, the change in an index’s constituents is generally announced to the public, before the swap actually takes place. If a company is being added to the S&P 500, that’s probably considered good news, and can make investors feel more confident in that company’s potential. Conversely, if a company is being dropped from an index, it may be a sign that things aren’t going so well.

That gives some traders an opening to take advantageous positions. Let’s say that an announcement is made that Firm X is being added to the Dow Jones Industrial Average, taking the place of another company. That’s big news for Firm X, and means that it’s likely Firm X’s stock price will go up.

Traders, if they have the right tools, may be able to quickly buy up Firm X shares the next day, and potentially, make a profit if things shake out as expected.

How is this different from regular front running? Because the information was available to the public — there was no secret, insider knowledge that helped traders gain an edge.

The Takeaway

Front-running is the illegal practice of taking non-public information that is likely to impact the price of a certain asset, then placing a trade ahead of that information becoming public in order to profit. Front running is similar to insider trading, although the latter generally involves an individual investor who profits from internal company information.

Fortunately, there are plenty of ways to profit in the markets without resorting to fraudulent activity like front running.

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Why is front-running illegal?

Front running is illegal for a few reasons. First, it’s a form of cheating the market, by using non-public information for a gain. Second, in the case of institutional front running, it’s a violation of a broker’s fiduciary duty to a client.

How can I identify if my trades have been affected by front running?

Unfortunately, owing to the non-public nature of the information that typically leads to front-running, it’s very difficult for individual investors to determine whether or not their own trades have been impacted by a front-running event. Financial institutions have more tools at their disposal to detect incidents of front running.

Are there any technological solutions or tools available to detect and prevent front running?

Yes. With so many traders using remote terminals to place trades since the pandemic, trade surveillance technology and trade reconstruction tools are more important than ever. Fortunately, financial institutions have the resources to employ these tools, and other types of algorithms, to monitor the timing of different trades in order to identify front runners and front running.

Photo credit: iStock/Drazen_

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