Term · Risks & Red Flags
Idiosyncratic Risk
In briefIdiosyncratic risk is the company-specific, unsystematic part of risk that does not stem from general market movements. For small stocks it is often high but, unlike market risk, it can be reduced considerably through diversification across many individual stocks.
Definition
Idiosyncratic risk is the company-specific part of investment risk that does not stem from general market movements. It arises from factors such as management, products, customers, or individual events at a company. Unlike systematic market risk, it can be reduced considerably through diversification across many stocks.
How it is calculated
Formula. Total risk = Systematic risk + Idiosyncratic risk
Why it matters for small caps
For individual small stocks, idiosyncratic risk is often high, because revenues and success may be tied to a few customers, products, or people. A diversified portfolio dampens this stock-specific share.
Common misreadings
- Idiosyncratic risk is often lumped together with market risk, even though only the stock-specific part can be diversified away through broad spreading.
In the process
Frequently asked
What is the difference from systematic risk?
Systematic risk affects the entire market and cannot be diversified away; idiosyncratic risk is stock-specific and can be reduced through spreading.
How do you reduce idiosyncratic risk?
Through diversification across many individual stocks, sectors, and regions, so that individual company-specific setbacks have less of an impact.
Why is it especially high for micro caps?
Because small companies often depend on a few customers, products, or key people, so that individual events have a disproportionate effect.
Related terms
Education only, not investment advice. Ranges and thresholds are didactic orientation values, not an official standard.