Concentration risk is the danger of holding too much of your portfolio in a single stock, sector, issuer, or asset class. It magnifies losses when that concentrated bet moves against you. SEBI directly limits concentration in mutual fund and SIF portfolios to protect investors.
What is Concentration Risk?
Concentration risk occurs when a portfolio is overly exposed to a single investment, issuer, sector, or asset class. If that concentrated position performs poorly, it can cause disproportionately large losses to the overall portfolio.
The fundamental principle of diversification — "don't put all your eggs in one basket" — directly addresses concentration risk. A well-diversified portfolio limits the damage any single bad investment can cause.
In Simple Terms
If a fund puts 40% of its money into one company's stock and that stock falls 50%, the portfolio loses 20% just from that one position. SEBI's limits prevent any single bet from becoming too large.
Types of Concentration Risk
1. Single-Stock Concentration
Holding an excessive percentage of the portfolio in one company. If that company faces fraud, regulatory action, management change, or business disruption, the impact on the portfolio is outsized.
2. Issuer Concentration
Holding debt and equity from the same issuer across instruments. Total exposure to a single corporate group can be high even if individual instrument limits appear compliant.
3. Sector Concentration
Over-allocation to a single sector (e.g., banking, IT, pharma). A sector-wide event — regulatory change, commodity price shock, or policy shift — can hurt all holdings simultaneously.
4. Asset Class Concentration
Holding too much in one asset class (e.g., all equity, all debt). A market-wide equity sell-off or credit event impacts the entire portfolio without diversification from other asset classes to cushion the blow.
SEBI Regulations on Concentration Risk
SEBI directly addresses concentration risk through investment limits prescribed in its Mutual Fund and SIF regulations:
Single Issuer Equity Limit
A scheme shall not invest more than 10% of its NAV in securities of a single company. This can be extended to 12% with trustee approval but requires disclosure in the Scheme Information Document.
Group Company Limit
Total investment in all companies belonging to the same group shall not exceed 20% of NAV, extendable to 25% with trustee approval.
Portfolio Overlap Limit (2026 Regulations)
SEBI has mandated that sectoral and thematic funds must limit portfolio overlap to 50% with any other equity scheme of the same AMC. This prevents two "different" funds from effectively being the same portfolio.
Unrated Debt Limits
A scheme shall not invest more than 10% of NAV in unrated debt from a single issuer. Total investment in unrated debt instruments across all issuers is capped at 25% of NAV.
Money Market Instrument Limit
A scheme shall not invest more than 30% of its net assets in money market instruments of a single issuer. This limit does not apply to government securities, treasury bills, and CBLOs.
REIT/InvIT Limits (SIF-specific)
A SIF strategy shall not invest more than 10% of its NAV in REIT/InvIT of a single issuer, and all its investment strategies combined cannot own more than 20% of units issued by a single issuer.
How Concentration Risk is Measured
Portfolio Weight Analysis
Examining what percentage of the portfolio is in each stock, sector, or issuer. A stock with more than 10% weight signals concentration risk.
Herfindahl-Hirschman Index (HHI)
A statistical measure of portfolio concentration. Higher HHI means more concentration. Lower HHI indicates broader diversification.
Sector Allocation Review
Monitoring what percentage of the portfolio is in each sector. Excessive sector allocation (e.g., 50%+ in banking) signals sector concentration risk.
Portfolio Overlap Analysis
Comparing stock-level holdings between two portfolios to identify overlap. High overlap means two funds are nearly identical despite different names or mandates.
Concentration Risk vs Diversification
| Aspect | Concentrated Portfolio | Diversified Portfolio |
|---|---|---|
| Number of Holdings | Few (5-10 stocks) | Many (30-80+ stocks) |
| Single Stock Impact | Very high (20-30% of portfolio) | Low (1-3% of portfolio) |
| Sector Risk | High if sector-heavy | Spread across sectors |
| Upside Potential | High (if right) | Moderate but consistent |
| Downside Risk | Very high (if wrong) | Limited by diversification |
Concentration Risk in SIF Strategies
SIF strategies must manage concentration risk within SEBI's prescribed limits. Fund managers also self-impose risk limits to ensure portfolios remain adequately diversified:
Equity Long-Short Fund
Long positions must comply with 10% single-issuer limits. Short positions via derivatives also require careful monitoring to avoid concentrated directional bets on a single stock.
Sector Rotation Long-Short Fund
Concentrated in up to four sectors by design. Within those sectors, individual stock limits still apply. Sector concentration is intentional and disclosed — the fund's ISID details the sectors and their weight limits.
Hybrid Long-Short Fund
Invests across equity, debt, REITs, and InvITs. The multi-asset nature reduces asset-class concentration. Issuer limits apply within each asset class.
Important Note for Investors
While SEBI limits control issuer-level concentration, investors should also check their own portfolio-level concentration across multiple funds — if several funds hold the same top stocks, the overall portfolio may still be highly concentrated in those names.
Definition: Excessive exposure to a single stock, issuer, sector, or asset class
SEBI Single-Issuer Equity Limit: Max 10% of NAV (extendable to 12%)
SEBI Group Company Limit: Max 20% of NAV (extendable to 25%)
Portfolio Overlap Limit: Max 50% between two equity schemes (sectoral/thematic)
Mitigation: Diversification across issuers, sectors, and asset classes
Sources: SEBI MF Regulations, SEBI Circular (2016), Economic Times (2025)