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Lesson in Course: Stocks (beginner, 8min )

We've heard of the movie "The Big Short." What is short-selling and does it apply to us?

Short-selling is traditionally used by Wallstreet and professional investors to bet against a stock or company. Short-selling, going short, is the opposite of buying shares or going long. Buying has an unlimited upside since there is no ceiling to the share price and a limited downside since the lowest price a share can drop to is $0. As opposites, shorts have an unlimited downside and a limited upside—this inverse payoff structure is what makes short-selling inherently more riskier.

How does it work?

Investors short-sell a stock by paying their brokerage a fee to borrow shares and sell the shares at the current market price. They then need to return the borrowed stock at some point and will make a profit if the price is lower when they buy it back. 

Tap for an example

Here's an example of how Melvin Capital, a hedge-fund famous for heavily betting against GME, would go about shorting $GME. The firm would go to a broker and borrow 100,000 shares of $GME at $35 per share and sell it right away for a cash gain of $3.5 million. If $GME ends up dropping down to $8 a share, then the fund only needs to spend $800,000 to buy back the 100,000 shares—bagging a profit of $2,700,000 minus what the brokerage charges to lend the shares. Alternatively, if $GME reached $100 per share, Melvin would have to buy 100,000 shares back for $10,000,000, resulting in a loss of $7,300,000. 

Tap for a video about short selling

Short interest

Short interest represents the amount of shares that have been sold short and can be seen as an indication of market sentiment.

GME's short interest had reached 140% at one point during the meme stock bubble. How can GME’s short interest be over 100%? Let's assume the broker lends 100 shares of GME to Hedge-fund1. HF1 shorts and sells those shares. The broker can then lend 40 of those same shares to HF2, which also decides to short GME. In this case, the original 100 shares created a short position of -140 shares.

Short squeeze

To short stock, brokers require the use of a margin account. If the price of a shorted stock rises, investors who bet against it will start to see losses. They will end up cutting their losses by covering their shorts or buying back the shares owed to the broker. 

When the investors can’t meet margin requirements or the stock price rises too rapidly, the brokerage can automatically cover short positions. This is usually forced when the risk of mounting losses is unmanageable. The forced buying from covering shorts continues to raise the stock price which increases the losses for other short-sellers and the cycle continues. This feedback loop causes a short-term spike in the stock price. Learn more about what happened to GameStop with this video.

It's incredibly expensive and risky to short stocks and it’s to be avoided. Instead, if we want to speculate on a stock price going down, we should buy put options. Check out our lesson on put options to learn more!


What is short-selling (going short)?

Short-selling is when investors bet against a stock by borrowing shares of the company from their brokerages and sell it right away. The short-seller will then eventually buy back the shares to return, hopefully at a lower price.

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