I was just looking at some friends discussing stock investment issues and found that many people actually don’t understand what par value and market price are; these two concepts are often confused. Today I want to talk about this topic, especially the concept of stock par value, which is easy to overlook but very important.

Let me start with an interesting quote, supposedly from Cervantes: "Only fools confuse value with price." This sentence is particularly meaningful for investors. When we talk about a stock’s price and its value, we are actually talking about two different things. Many value investors are looking for undervalued assets, buying them at a lower price, and waiting for the market to recognize their true worth again.

So what is par value? Simply put, a stock’s par value is the starting point when the company issues shares. Its calculation is very straightforward: the company’s registered capital divided by the total number of shares issued equals the par value per share. For example, if a company’s registered capital is 4 million euros and it issues 50k shares, then the par value per share is 80 euros. This number is recorded in the company’s articles of incorporation.

Par value and market price often differ greatly. Take Caixabank as an example: its registered capital is 50k euros, distributed over 806 million shares, so the par value per share is 1 euro. But in the market, the stock price might be 3.29 euros or higher, making the market capitalization calculated from that far exceed the registered capital. This demonstrates the power of market pricing—it reflects investors’ expectations for the company’s future, not just the book value.

There’s also a concept that’s easy to confuse: book value. Book value is calculated by dividing the company’s net assets (registered capital plus accumulated profits or losses) by the total number of shares. This indicator seems more “real,” but in practice, it’s rarely used in investing because it doesn’t truly reflect market value.

For a nominal asset (activo nominal), the par value is a fixed reference point. But a company can change this par value through capital increases or decreases. For example, Unicaja Bank once reduced its par value from 1 euro to 0.25 euros, usually to adjust its capital structure or cover losses.

Interestingly, some U.S. companies issue no-par stock, but in Europe, especially in Spain, laws require each share to have a clear par value, which must be explicitly stated in the articles of incorporation.

The efficient market theory suggests there are three possible market states. The first is weak-form efficiency, where prices are unrelated to past data, and you can only analyze fundamentals. The second is semi-strong efficiency, where all public information is already reflected in prices, and only insiders can beat the market. The third is strong-form efficiency, where even non-public information is priced in, making passive investing the best strategy. But historical investors like Warren Buffett and Peter Lynch have shown that markets are not always efficient, so that quote still holds: value and price are indeed not the same thing.

For ordinary investors, understanding par value is important because it helps you grasp a company’s capital structure. When you trade on a platform, you usually see only the market price because stock trading occurs in the secondary market. But if you want to understand a company more deeply, knowing its par value, registered capital, and market value can help you make more informed decisions. That’s why many seasoned investors check official company information to understand the true capital composition behind each stock.