What is concentration risk?

📘 In Brief Concentration risk arises when a large portion of assets or income depends on a single investment, a single customer, or a single industry. If that one position fails, the damage hits the entire portfolio or business with full force because no other areas can cushion the loss. Typical examples include an employee who invests all their money in their own company’s stock, or a bank that extends nearly all its loans to the same real estate developer. The risk lies in the lack of diversification: instead of bearing many small, independent risks, everything is concentrated on one card. When an unexpected event occurs—such as a fraud scandal or an industry downturn—the loss is not only high but often existential. That is why regulators and prudent investors deliberately require limits on such concentrations to make the overall situation more stable and predictable. 🔍 Why It Matters Concentration risk refers to the excessive concentration of assets or exposures on a single debtor, industry, or region. It arises when a default or crisis in that area causes disproportionately high losses because diversification is lacking. In banking, it is limited by regulatory caps such as large exposure limits to avoid systemic imbalances. For investors, concentration risk means that portfolio performance depends heavily on a few positions. One example is an excessively large share of a single stock in the overall portfolio. The result is increased volatility and a higher risk of tota …