The 8-Stock Problem — Why Your 3 Large-Cap Funds Are Almost The Same Fund

SEBI mandates that large-cap funds invest at least 80 percent of their corpus in the top 100 listed companies by market capitalisation. This 80 percent floor combined with risk management constraints means almost every large-cap fund clusters around the largest 15 to 20 names. The top 10 large-cap funds in India by AUM hold the same 8 core stocks: HDFC Bank, Reliance Industries, ICICI Bank, Bharti Airtel, TCS, Infosys, Larsen and Toubro, and Axis Bank or Kotak Mahindra Bank. These 8 stocks alone make up between 35 and 45 percent of most large-cap fund portfolios. The remaining 35 to 45 percent of holdings show some differentiation but typically draw from another 20 to 25 large caps that everyone owns in varying weights. The result is that two different large-cap funds have portfolio overlap of 55 to 62 percent on average and produce returns that diverge by less than 2 percent in most years.

Portfolio overlap measures the percentage of a fund's holdings that are common with another fund's holdings, weighted by allocation. The calculation: for each stock held by both funds, take the minimum of the two weights; sum these minimums across all common stocks. For example if Fund A holds HDFC Bank at 9 percent and Fund B holds HDFC Bank at 7 percent, the overlap from this stock is 7 percent. Sum the minimums across all common holdings. The result is the percentage of the two funds that effectively replicates each other. Industry standard tools like Value Research and Morningstar India compute this from monthly AMFI portfolio disclosures. Overlap above 60 percent means the two funds are economically the same exposure, and holding both is wasteful from a diversification standpoint.

Yes for two reasons. First, diversification benefit is negligible because the underlying holdings are largely identical. The portfolio of three large-cap funds with 60 percent average pairwise overlap effectively gives you 1.4 to 1.6 funds worth of diversification, not 3. Second, you pay three expense ratios on the same exposure. If each fund charges a 1.7 percent total expense ratio on a regular plan, and the three funds are 60 percent overlapping, the effective duplicate cost on the overlapping portion is approximately 1.02 percent on 60 percent of your capital. Over 20 years of compounding, holding 3 overlapping funds instead of 1 fund plus a Nifty 50 index fund can cost 15 to 22 lakh rupees on a 50 lakh portfolio. The smarter structure is one large-cap fund plus a Nifty 50 index fund plus optionally one flexi-cap fund for exposure outside the top 100.

The lowest pairwise overlaps as of March 2026 portfolio disclosures are between funds that take active sector bets versus index-hugging funds. Funds that lean towards public sector banks like Canara Robeco Bluechip Equity overlap less with funds that lean private financials like Axis Bluechip. Funds with higher consumer discretionary weight like Mirae Asset Large Cap overlap less with infrastructure-heavy funds. But these are exceptions. Even the most differentiated active large-cap fund pairs in India have overlap of around 45 to 50 percent because the SEBI 80 percent floor forces clustering at the top of the market cap range. The only way to truly own a different large-cap exposure is to buy a Nifty Next 50 index fund which holds the 51st to 100th largest companies that active large-cap funds typically underweight or avoid.

The difference between regular and direct plan expense ratios is typically 0.8 to 1.2 percent per year on large-cap funds. On a 10 lakh rupee investment held for 20 years compounding at 12 percent gross, this 1 percent difference translates to approximately 17 to 22 lakh rupees of additional terminal wealth in direct plan. The math: 10 lakh at 12 percent for 20 years grows to 96.5 lakh. The same 10 lakh at 11 percent grows to 80.6 lakh. The 15.9 lakh difference is entirely the result of avoiding distributor trail commission. For larger investments and longer horizons the absolute savings are larger. On a 50 lakh portfolio over 30 years the direct plan saves 1.5 to 2 crore rupees. Switching from regular to direct does not trigger capital gains tax if you remain in the same scheme, only the plan changes.

Three reasons. First, expense ratio. A Nifty 50 index fund charges 0.05 to 0.30 percent total expense ratio versus 1.5 to 2.1 percent for active large-cap funds. The drag of an extra 1.5 percent per year compounds dramatically over 20 to 30 years. Second, consistency. Active large-cap funds underperform the Nifty 50 over rolling 5 year periods in around 65 to 75 percent of cases as per SPIVA India scorecards. The probability of picking the active fund that beats the index over your investment horizon is roughly one in three. Third, behavioural simplicity. Index funds remove the temptation to switch funds based on short-term performance, which itself destroys returns. The case for active large-cap funds exists only for very specific market regimes and only for the small minority of funds with structural alpha. For most investors a Nifty 50 index fund is the default that beats their actual allocation over time.

Closet indexing is when an actively managed fund holds a portfolio that is statistically indistinguishable from its benchmark index while charging active management fees. Active share is the standard metric for detecting it. Active share above 60 percent indicates genuine active management. Below 30 percent indicates closet indexing. In Indian large-cap funds, several large AUM schemes show active share in the 25 to 40 percent range, meaning 60 to 75 percent of the portfolio mirrors the Nifty 50. Investors in these funds pay 1.7 percent expense ratio for what is effectively a 0.15 percent index fund. The funds most exposed to this critique are typically the largest AUM schemes because size itself forces convergence to the benchmark to avoid market impact when trading. AMFI does not publish active share data, but it can be computed from monthly portfolio disclosures cross-referenced with Nifty 50 index weights.

Three free tools. First, Value Research Online has a portfolio overlap tool where you input two scheme codes and see the overlap percentage and common holdings. Second, Morningstar India provides similar overlap analysis in its scheme research pages. Third, you can manually download the monthly portfolio disclosure PDFs from each AMC website or AMFI portal, cross-reference the top 30 holdings, and compute overlap using the minimum-weight method described in the FAQ above. AMFI requires AMCs to publish monthly portfolio disclosures by the 10th of the following month under the Securities and Exchange Board of India regulations. The Excel format from AMFI portal is the most reliable source. For investors holding 3 or more funds, doing this exercise once per year reveals whether your portfolio is genuinely diversified or just paying multiple TERs on similar exposure.

SEBI's October 2017 scheme categorisation rules mandate that a large-cap mutual fund must invest at least 80 percent of its total assets in equity and equity-related instruments of large-cap companies, defined as the top 100 companies by full market capitalisation. The list of top 100 is updated by AMFI every six months based on average market cap of the prior six months. This 80 percent floor combined with risk management constraints means active large-cap fund managers have limited room to differentiate. The remaining 20 percent can go into mid-cap, small-cap, debt, cash or international equity. Most active large-cap funds keep this flexibility allocation in mid-caps to add alpha, but a 20 percent mid-cap allocation in a large-cap fund creates a misleading risk profile for investors who chose the fund for stability. Read the scheme document for the exact flexibility used by each fund.

For most investors yes, with caveats. The case to switch is strongest if your current large-cap fund has underperformed the Nifty 50 over the trailing 5 years, has a TER above 1.5 percent, has active share below 40 percent indicating closet indexing, or if you hold multiple large-cap funds with overlapping portfolios. The case to stay in an active large-cap fund exists only if the fund has consistently delivered alpha above its expense ratio over rolling 5 year periods, has a differentiated portfolio with active share above 60 percent, and is managed by a stable team you trust. Tax implications matter. Switching triggers capital gains, so if you have a large unrealised long-term gain, the tax cost of switching might exceed the long-term saving. The cleanest path for most investors is direct STP from active large-cap to Nifty 50 index fund over 6 to 12 months to spread the tax impact, while routing all fresh investments to the index fund.

Often yes for the diversification problem but not always for cost. Flexi-cap funds can invest across large, mid and small caps without minimum allocation requirements in any single segment. The flexibility allows the manager to overweight wherever risk-reward looks best. In practice, most flexi-cap funds in India end up with 65 to 80 percent large-cap allocation because of liquidity constraints and risk management. This means a flexi-cap fund often gives you only marginal mid-cap and small-cap exposure on top of a portfolio that overlaps with large-cap funds anyway. The expense ratio is similar to large-cap funds at 1.5 to 2 percent. The right way to use flexi-caps is as a replacement for the mid-cap allocation in your portfolio, not as a substitute for large-cap exposure. Read the detailed analysis of large-cap bias in flexi-cap funds before substituting.