U.S. Small Cap in the context of portfolio diversification in 2026

One of the defining themes of recent years has been extreme market concentration in the US. At the beginning of 2026, many investors are asking themselves what meaningful diversification beyond the dominant megacaps might look like, and what role the small-cap segment could play. In this ChampionsCall, Mathieu Sirois, President and Senior Portfolio Manager at Van Berkom, provides a solid analysis of the US small-cap market. As a specialised boutique, Van Berkom's team focuses exclusively on the small-cap segment. This deliberate focus enables a depth of analysis that goes far beyond standard research.