What is short selling?

Short selling is a strategy to profit from a falling share price. Instead of the usual sequence of buying low and selling high, a short seller reverses the order: they sell first — using shares borrowed from someone else — and aim to buy back later at a lower price, returning the borrowed shares and pocketing the difference.

Here is the mechanics in simple terms. A short seller borrows shares (through a regulated securities-lending arrangement) and sells them in the market at, say, Rs 100. If the price later falls to Rs 80, they buy the shares back, return them to the lender, and keep roughly Rs 20 per share (before costs). If they are right about the direction, they profit as the stock declines.

The catch is that the risk profile is asymmetric and dangerous. When you buy a stock, the most you can lose is what you paid — the price can only fall to zero. When you short a stock, your potential loss is theoretically unlimited, because a price can keep rising with no ceiling. A short that moves against you grows more painful the higher the stock climbs, and a sharp rally can force shorts to buy back in a hurry — a short squeeze — pushing the price even higher.

Short selling is tightly regulated. On the Pakistan Stock Exchange, short sales must follow the exchange's rules, including using the proper securities lending and borrowing framework rather than selling shares one does not own or has not borrowed (so-called naked short selling, which is prohibited). Regulators monitor short activity closely and can impose restrictions during periods of stress.

Why does short selling exist at all? Supporters argue it serves useful functions: it adds liquidity, helps price discovery by letting negative views be expressed, and can expose over-valued or troubled companies. Critics worry it can amplify declines and be misused. Most markets, including Pakistan's, permit regulated short selling while guarding against abuse.

For ordinary investors, short selling is an advanced, high-risk technique rather than a routine tool. The unlimited-loss profile, borrowing costs, and the discipline required to manage positions make it unsuitable for beginners. Understanding it, however, helps you interpret market commentary — when analysts mention "short interest" or a "short squeeze," they are describing these borrowed-and-sold positions and the scramble that can occur when they unwind.