The Case for Rebalancing Growth Portfolios in Light of Gabelli Small Cap Underperformance in Q3 2025

The Gabelli Small Cap Growth Fund (GABSX) has long been a staple for investors seeking exposure to high-growth small-cap equities. However, its underperformance in Q3 2025-falling behind key benchmarks like the Russell 2000 Total Return Index and the S&P SmallCap 600 Total Return Index-raises critical questions about its alignment with evolving macroeconomic and market leadership dynamics. As of October 31, 2025, the fund posted a year-to-date (YTD) return of 5.24%, lagging behind the Russell 2000's 12.4% gain during the same period. This divergence underscores the need for investors to reassess their growth portfolios in light of shifting market fundamentals.

Macroeconomic Tailwinds and Small-Cap Dislocation

The Q3 2025 macroeconomic environment was defined by the Federal Reserve's rate-cut cycle and a surge in speculative momentum around artificial intelligence (AI) infrastructure. Lower interest rates typically benefit small-cap stocks, which are more sensitive to economic cycles and discount rate changes. Yet, the Gabelli fund's underperformance suggests a misalignment with the sectors driving market gains. According to a report by Pzena, small-cap stocks traded near historic lows relative to large-cap peers, with valuation disparities creating opportunities for long-term investors. However, the fund's portfolio, which includes holdings like Mueller Industries, Inc. and Gorman-Rupp Co. classified in the manufacturing sector, appears to lack exposure to the AI and semiconductor themes that dominated Q3.

The Russell 2000's 12.4% gain was fueled by speculative momentum in high-growth tech firms, particularly those supplying AI infrastructure according to Osterweis. In contrast, the Gabelli fund's focus on "traditional" small-cap companies with strong balance sheets and niche franchises as per Gabelli's website left it vulnerable to a market skewed toward speculative, high-multiple stocks. This highlights a broader trend: small-cap value strategies, including the Cooke & Bieler Small Cap Value Composite, also underperformed, returning 4.16% gross of fees against the Russell 2000 Value Index's 12.60% as reported by Cooke & Bieler.

Strategic Missteps and Sector Exposure

The fund's investment philosophy emphasizes companies with "exceptional revenue expansion and earnings growth" as stated in the fund's prospectus, yet its Q3 contributors-such as Gorman-Rupp Co.-operate in industrial manufacturing, a sector that has historically lagged during AI-driven rallies. While the fund's manager, Mario Gabelli, CFA, has a strong track record, the portfolio's sector allocation failed to capitalize on the Q3 shift toward technology and semiconductors. This misalignment is particularly striking given the fund's mandate to target "expanding industries", a category now dominated by AI infrastructure.

Moreover, the fund's underperformance reflects broader challenges in the small-cap space. High debt levels in small-cap companies and investor concentration in the "Magnificent Seven" and other large-cap tech stocks exacerbated volatility as detailed in Pzena's report. For growth-oriented investors, this suggests that traditional small-cap strategies may no longer suffice in a market increasingly driven by thematic, high-risk bets.

The Case for Rebalancing

The Q3 2025 experience offers a compelling case for rebalancing growth portfolios. First, investors should prioritize exposure to sectors aligned with AI and semiconductor demand, where small-cap innovation is most pronounced. Second, diversification across market capitalizations may mitigate risks associated with overconcentration in underperforming small-cap value strategies. Third, while the Gabelli fund has historically outperformed in 16 of 21 years, its recent underperformance signals a need to evaluate whether its long-term strategy remains compatible with current market dynamics.

Rebalancing does not necessitate abandoning small-cap growth entirely but rather recalibrating allocations to reflect the new leadership. For instance, investors might consider augmenting their portfolios with small-cap growth funds that explicitly target AI infrastructure or semiconductor supply chains, areas where the Gabelli fund has shown limited exposure as noted on the fund's website.

Conclusion

The Gabelli Small Cap Growth Fund's Q3 2025 underperformance is a microcosm of broader market shifts. As macroeconomic conditions and leadership dynamics evolve, investors must adapt their strategies to align with the drivers of growth. Rebalancing portfolios to emphasize AI-related small-cap opportunities, while hedging against overexposure to traditional industrial sectors, could position investors to capitalize on the next phase of market expansion. In a landscape defined by rapid technological change, flexibility and strategic reallocation are no longer optional-they are imperative.