Many investors buy several equity mutual funds because the funds have different names, fund managers, investment styles, or categories. On paper, this can look like diversification.
But different funds can still own many of the same companies.
This is known as fund overlap.
The issue is not automatically a problem. Two funds can share stocks and still have different portfolios, different weights, different strategies, and different risk levels. However, a high overlap can mean that an investor has less diversification than expected.
This matters because the number of mutual funds in a portfolio does not by itself show how diversified that portfolio is.
An investor who owns four or five equity funds may still have a large part of the total portfolio linked to the same companies.
The first step is therefore simple: look beyond the fund names and check the actual stocks held by each fund.
Different funds can own the same companies
Equity funds often have different mandates. One fund may focus on large companies. Another may invest across market sizes. A third may focus on tax-saving investments. A fourth may focus on smaller companies.
Despite these different labels, their portfolios can still have common stocks.
This happens partly because large and well-known companies are held by many professional fund managers. A fund manager may choose a particular company because of its size, business position, earnings outlook, valuation, or role within an industry.
As a result, the same company can appear in several funds at the same time.
Recent data cited in the earlier analysis showed that names such as ICICI Bank, HDFC Bank, SBI, Bharti Airtel and Reliance Industries appeared across multiple fund categories, including large-cap, mid-cap and small-cap funds.
This does not mean every fund holds all of these companies. It also does not mean that such overlap makes a fund unsuitable. It simply shows why fund category names should not be treated as proof of complete diversification.
The number of common stocks tells only part of the story
A simple way to check overlap is to count the stocks that two funds have in common.
Consider this example from the earlier data.
| Measure | Fund A | Fund B |
|---|---|---|
| Total stocks | 40 | 55 |
| Common stocks | 18 | 18 |
| HDFC Bank weight | 7% | 5% |
| ICICI Bank weight | 6% | 4% |
| Reliance weight | 5% | 3% |
Here, the two funds have 18 common stocks.
That number is useful, but it does not tell the full story.
The more important question can be: How much money do both funds have in those common stocks?
For example, HDFC Bank has a 7% weight in Fund A and a 5% weight in Fund B. ICICI Bank has a 6% weight in Fund A and a 4% weight in Fund B. Reliance has a 5% weight in Fund A and a 3% weight in Fund B.
The economic exposure can therefore be much more important than the simple count of common companies.
Stock count and weighted overlap are different
There are two useful ways to look at fund overlap.
The first is the number of common stocks. This is easy to understand. If two funds each have 50 stocks and 20 are the same, the investor knows that 20 companies appear in both portfolios.
The second is weighted overlap.
Weighted overlap looks at the portfolio weight assigned to the common stocks. For each shared stock, the lower of the two fund weights can be used. Those amounts are then added to estimate the portion of one portfolio that has a matching exposure in the other.
This approach can give a more useful picture of concentration.
Imagine that two funds share 15 companies. If those 15 companies have very small weights, the practical overlap may be modest.
Now imagine that the same 15 companies make up a large part of both portfolios. The economic overlap can then be much higher.
This is why investors should avoid judging diversification from the number of common stocks alone.
What recent overlap data shows
The earlier data included several useful examples.
One July 2026 comparison showed 5 common stocks out of 27 and 85 holdings, with about 8.9% weighted overlap.
The figures show an important point. Two portfolios can have a different number of total holdings and still have some common exposure.
The same earlier analysis cited May 2026 data that showed large-cap funds averaged roughly 41% overlap with other large-cap funds, while small-cap funds averaged about 13%.
These figures should be read in their proper context. An average is not a measure of every individual fund pair. Actual overlap can vary considerably from one pair of funds to another.
Fund portfolios also change. A fund manager can buy a new stock, reduce an existing position, or remove a company from the portfolio. Therefore, an overlap figure is tied to the portfolio date used for the calculation.
Why large-cap funds can show more overlap
Large-cap funds can naturally have a higher level of common exposure.
The reason is fairly straightforward.
There is a limited group of very large listed companies that meet the size and liquidity characteristics sought by many large-cap fund managers. When several managers select from the same large-company universe, some common holdings are expected.
This does not necessarily mean the funds follow the same strategy.
Two managers can own HDFC Bank, for example, but assign different weights to it. They can also own very different companies outside that common position.
One fund may hold 5% in a particular stock, while another may hold 8%. Their sector allocations, cash levels, smaller positions, and valuation views can still differ.
Therefore, common ownership should be treated as one part of portfolio analysis rather than as a complete measure of similarity.
Category labels do not guarantee diversification
Investors sometimes assume that different categories automatically create different exposures.
That assumption can be unsafe.
Consider a portfolio with a large-cap fund, a flexi-cap fund, an ELSS fund and a mid-cap fund.
The four funds have different mandates. Yet some companies can appear in more than one fund.
A flexi-cap fund has more freedom across market segments. An ELSS fund also has a broad equity mandate, subject to its tax-saving structure. A large-cap fund has a more specific focus on larger companies.
Their portfolios can therefore overlap even when their category names are different.
A mid-cap fund can also share some companies with another category, particularly where a company sits close to the relevant market-cap boundaries or where different fund mandates allow similar stock choices.
The practical lesson is simple: fund category is a starting point, not proof of diversification.
Overlap can affect portfolio concentration
Suppose an investor puts equal amounts into four funds.
If the funds have almost no common stocks, the investor may have exposure to a wider group of companies.
But suppose all four funds have significant exposure to the same few companies.
The investor may then have a much larger combined exposure to those companies than the number of funds suggests.
For example, if three funds each hold a major position in the same bank, the investor has exposure to that bank through all three funds.
The investor does not own the bank directly three times. But the economic exposure can still be repeated across the funds.
This is the central reason fund overlap deserves attention.
Sector overlap also matters
Stock overlap is not the only issue.
Two funds may own different companies but still have large exposure to the same sector.
For example, Fund A may hold one private bank while Fund B holds another private bank. The stocks are different, but both portfolios have exposure to the banking sector.
The same idea applies to technology, financial services, energy, consumer businesses and other sectors.
This creates another layer of portfolio analysis.
An investor can therefore examine both company-level overlap and sector-level overlap.
The first asks whether the same companies appear in several funds.
The second asks whether different companies still place the portfolio at risk from the same broad sector trend.
Overlap is not automatically a bad thing
It is important not to treat overlap as a warning sign in every case.
A common stock may appear in several funds because several managers independently regard the company as suitable for their respective mandates.
Also, the same stock can have different weights in different funds.
Two funds may share ten companies but have very different allocations across those companies. Their remaining holdings can also be very different.
The quality, valuation, business outlook and risk of each company are separate questions.
Therefore, a high overlap figure does not by itself establish that a fund is good or bad, suitable or unsuitable.
It simply tells an investor that the portfolios have a meaningful degree of common exposure.
Portfolio overlap can change
Another important point is timing.
Mutual fund portfolios are not fixed forever.
Fund managers can change holdings as their views, valuations, company conditions and portfolio needs change. A stock that appears in two funds today may appear in only one fund later.
The reverse can also happen.
For this reason, investors should look at the date of the portfolio data before drawing conclusions from an overlap calculation.
A comparison based on July 2026 data should not be treated as a permanent description of those funds.
The earlier figures should therefore be viewed as a snapshot of the relevant portfolios at the stated dates.
How investors can check their own funds
The process is relatively simple.
Start with the latest disclosed portfolios of the funds.
Write down the holdings of each fund and their portfolio weights. Then compare the lists.
The first result is the number of common stocks.
The next result is the weight assigned to those common stocks.
This can then be repeated for every pair of funds.
For four funds, for example, the useful comparisons are Fund A against Fund B, Fund A against Fund C, Fund A against Fund D, Fund B against Fund C, Fund B against Fund D, and Fund C against Fund D.
This produces a much clearer picture than simply counting the number of funds in the portfolio.
SEBI disclosures make this analysis possible
Mutual fund portfolio information is publicly disclosed under the applicable regulatory framework.
The earlier analysis referred to SEBI disclosure requirements for mutual fund portfolios, including holdings and portfolio weights.
This means investors can use disclosed portfolio data to examine common holdings rather than rely only on fund names or category descriptions.
The exact format and frequency of disclosures can depend on the applicable rules and the type of fund data involved. Investors should therefore use the latest available official disclosure when they perform a current comparison.
A simple way to read the results
An overlap analysis can be viewed through three questions.
The first question is: How many stocks are common?
The second is: How large are those positions in each fund?
The third is: How much of my total portfolio is exposed to the same companies?
The third question is especially relevant for an investor who owns several funds.
For example, an investor may own five funds and see only moderate overlap between individual pairs. But if the same few companies appear across four or five funds, the combined portfolio can still have material exposure to those names.
This is why pair-by-pair analysis and total portfolio analysis can both be useful.
What the numbers do not tell you
Overlap data has limits.
It does not tell an investor whether a stock is fairly valued.
It does not predict future returns.
It does not show whether a fund manager will change the portfolio.
It also does not establish that a higher-overlap portfolio will perform better or worse than a lower-overlap portfolio.
Past portfolio overlap is simply evidence about the holdings at a particular point in time.
Investment decisions require a wider review of the fund’s objective, costs, portfolio construction, risk, performance history, tax considerations and the investor’s own circumstances.
The bigger point for equity investors
Owning several mutual funds can create a sense of diversification. But fund count and stock count are not the same thing.
Three different funds can own many of the same companies.
Five funds can also have a large combined exposure to a smaller group of stocks.
The earlier figures show why this deserves attention. A July 2026 comparison had 5 common stocks out of 27 and 85 holdings, with about 8.9% weighted overlap. May 2026 data cited in the earlier analysis showed roughly 41% average overlap among large-cap funds and about 13% among small-cap funds.
These numbers do not describe every fund or every investor. They do, however, show that portfolio overlap can exist even when fund categories look different.
The most useful approach is therefore to look through the fund labels and examine the underlying holdings.
Conclusion
Fund overlap is easy to miss because mutual funds are usually presented as separate products.
A large-cap fund, a flexi-cap fund, an ELSS fund and a mid-cap fund may look different at first glance. Their actual portfolios can tell a more detailed story.
The number of common stocks provides a useful first check. Weighted overlap provides a deeper view. Combined portfolio exposure provides another important layer.
None of these measures is a complete investment judgment on its own.
For an investor who wants to understand true diversification, the key question is not simply “How many funds do I own?”
A more useful question is:
“How many different companies am I actually exposed to, and how much of my money depends on the same companies?”
That simple check can reveal portfolio concentration that may not be obvious from the fund names alone.
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