PENNYCALC RESEARCH / INVESTING
PennyCalc research · Updated · Dated SEC portfolio snapshots
Adding another fund can mean buying more of the same companies. We built this calculator to answer a practical question: if an S&P 500 fund, a total-market fund and a technology fund sit in the same portfolio, what do you actually own underneath?
In the default 50/50 VOO and VTI example, the ten largest companies account for 35.66% of the combined portfolio. Change the mix to see which exposures grow, which genuinely differ, and where the same company appears through several funds.
Dated findings · 2026-10-18
88.12% weighted company overlap. For each company held by both funds, we add the smaller of its two fund weights. This uses the disclosed portfolios and combines share classes belonging to the same company.
More funds can increase concentration. The ten largest companies represent 35.66% of an equal VOO/VTI portfolio. In the 60.00% VOO, 20.00% VUG, 20.00% VGT example, that rises to 45.27%.
Fixed examples from SEC holdings dated 2026-05-31 through 2026-07-31. These findings stay fixed when you change the calculator. Primary filings and calculation method · Link to these findings
LOOK THROUGH THE LABELS
Holdings snapshots: VOO ; VTI . Dated holdings, not live prices.
Combined weight after merging share classes.
Share of this portfolio in companies appearing in at least two selected funds.
Based on the available issuer identifiers.
For each shared company, add the smaller weight in the two funds. This compares the fund portfolios themselves, so changing your allocation or investment amount does not change a pair's overlap.
VOO + VTIVOO · VTI
88.12%Shared-company exposure, shown above, adds your entire combined position in each company held through two or more selected funds. Weighted pair overlap compares two funds by adding the smaller of their weights in each shared company.
These percentages answer different questions. Neither is a diversification score: a more concentrated portfolio can have a lower shared-company percentage. Check the ten largest companies and their weights alongside overlap. See the dated VOO/VTI example.
Trace any highlighted company from each fund to its reported classification. Flow width represents portfolio weight.
On smaller screens, the company cards below show each fund's contribution to the same combined result.
EXPLORE A COMPANY
See which funds contribute to its combined weight. The flow chart highlights those paths.
| Company | Portfolio weight | Dollars | Contribution from each fund |
|---|---|---|---|
| NVDA | 6.93% | $693 | VOO 3.76% · VTI 3.18% |
| AAPL | 6.23% | $623 | VOO 3.29% · VTI 2.94% |
| GOOGL / GOOG | 5.51% | $551 | VOO 2.92% · VTI 2.59% |
| MSFT | 4.06% | $406 | VOO 2.15% · VTI 1.91% |
| AMZN | 3.40% | $340 | VOO 1.81% · VTI 1.59% |
| AVGO | 2.62% | $262 | VOO 1.39% · VTI 1.24% |
| MU | 1.91% | $191 | VOO 1.01% · VTI 0.90% |
| META | 1.81% | $181 | VOO 0.96% · VTI 0.85% |
| TSLA | 1.74% | $174 | VOO 0.92% · VTI 0.82% |
| 1.44% | $144 | VOO 0.74% · VTI 0.70% | |
| AMD | 1.39% | $139 | VOO 0.73% · VTI 0.65% |
| 1.35% | $135 | VOO 0.71% · VTI 0.64% | |
| 1.19% | $119 | VOO 0.63% · VTI 0.56% | |
| INTC | 0.90% | $90 | VOO 0.51% · VTI 0.39% |
| 0.90% | $90 | VOO 0.47% · VTI 0.42% |
Cash, other assets and the net-asset residual: 0.24% ($24). All holdings enter the calculation; the table shows the largest 15 companies.
THE COMMERCIAL CONNECTIONS
Ownership is only one connection. Some of these companies also invest in one another's partners, supply their infrastructure, or sell them cloud capacity. Select a company to inspect a small, sourced set of relationships.
investment
Following OpenAI's recapitalization, Microsoft reported a stake valued at approximately $135 billion, roughly 27% on an as-converted diluted basis. This is the reported value of the stake on that date, not $135 billion of cash invested. The April 2026 amendment still describes Microsoft as a major shareholder.
Announced 2025-10-28 · Reported stake value at recapitalization
Read the primary source ↗cloud
The amended agreement keeps Microsoft as OpenAI's primary cloud partner, with OpenAI products shipping first on Azure subject to capability conditions. OpenAI can serve all products across other cloud providers; the Microsoft IP license is non-exclusive. This is not a claim of exclusive hosting.
Announced 2026-04-27 · Amended agreement announced
Read the primary source ↗SOURCES & CALCULATION
The calculator reads every disclosed common and preferred equity line in each source filing. Your allocation to a fund is multiplied by each company's weight in that fund. We then add those exposures across funds, combining share classes when they identify the same issuer.
Example: a 50% fund allocation multiplied by a 6% company weight contributes 3% of your total portfolio.
| ETF share class | Holdings date | Equity lines | Equity weight | Classified weight | Primary filing |
|---|---|---|---|---|---|
| VOO | 2026-06-30 | 506 | 99.75% | 98.59% | SEC NPORT-P ↗ |
| VTI | 2026-06-30 | 3,531 | 99.78% | 98.54% | SEC NPORT-P ↗ |
| VUG | 2026-06-30 | 147 | 99.96% | 99.41% | SEC NPORT-P ↗ |
| VGT | 2026-05-31 | 317 | 99.84% | 98.92% | SEC NPORT-P ↗ |
| VXUS | 2026-07-31 | 8,776 | 98.94% | 0.21% | SEC NPORT-P ↗ |
Classification coverage is incomplete. Sectors come from the fund issuer's June 30, 2026 portfolio schedule categories, not GICS. The exact-name crosswalk leaves unmatched holdings unclassified. Almost all VXUS equity weight is unclassified in this crosswalk, so the chart cannot provide a complete international sector breakdown.
Classification source: Vanguard's portfolio schedule filed with the SEC ↗. A classification date can differ from a fund's holdings date.
The remaining share of net assets includes cash, non-equity investments, derivatives, other assets and liabilities. It is retained as a residual rather than silently allocating it to equities. Company matching uses curated major-company aliases, then issuer LEI, then normalized issuer name. It does not infer parent-company ownership.
An S&P 500 fund and a total U.S. market fund have different mandates, but both can give substantial weight to the same large companies. For these dated VOO and VTI snapshots, the sum of the smaller company weight in each shared holding is 88.12%. That is a weighted overlap calculation, not a count of identical ticker symbols.
Adding a growth or technology fund changes the balance further. It can increase exposure to companies already prominent in a broad-market allocation, even though the portfolio contains more fund names. The most useful question is how the combined company weights change.
Our S&P 500 concentration analysis follows the largest security positions over time. This calculator answers a different question by combining your selected funds and grouping share classes into companies.
A reported sector label is one way to organize a portfolio. A company's commercial activities tell another part of the story. A retailer can also run a cloud business, and a chip company can supply infrastructure used by several competing platforms.
The company panels and relationship map make some of those connections visible. Business-activity tags describe the company as a whole; they are not a calculation of revenue attributable to AI, the market value of a cloud division, or an additional investment you own. An announced investment commitment is also different from money already funded.
Knowing where the portfolio is concentrated gives you a clearer view of what you own. The next question is when you will need to spend it. A long recovery can be manageable for money that stays invested, while withdrawals require selling assets along the way.
Use the historical investment and withdrawal calculator to choose a starting amount, a historical entry date and a withdrawal schedule. It shows the path the investment took and whether spending started before the recovery arrived.
Both funds contribute to your total economic exposure to that company. We add the portfolio weights once to show the combined exposure. The overlap statistic is the share of your portfolio invested in companies present in two or more selected funds, not an additional amount on top of your portfolio.
The labels are taken from a disclosed issuer portfolio schedule. They are not the licensed GICS classification system, and we do not infer a missing sector from a company's name. Unclassified holdings remain visible.
No. A relationship establishes a documented commercial or investment connection. It does not establish its financial materiality, the direction of future returns, or a causal relationship between stock prices.
No. It describes the exposures in the combination you select using dated source data. It does not assess your circumstances, forecast returns or select an allocation for you.