A customised ETF can defer tax when an eligible low-basis portfolio changes wrapper, while in-kind redemptions can improve the fund’s internal tax position. Treasury scrutiny now tests where legitimate continuity ends and engineered avoidance begins, raising the standard of proof for family offices.
A public ETF can begin as a private-wealth reorganisation. An investor contributes an already diversified portfolio of appreciated securities, receives shares in a listed fund and defers immediate federal gain if the Section 351 ETF conversion qualifies. Ownership, governance and basis change location. The securities and their embedded tax do not disappear.
Two provisions drive the result. Section 351 can defer gain when property is exchanged for stock under prescribed conditions. Section 852(b)(6) can prevent fund-level recognition when securities leave a regulated investment company through in-kind redemptions. Neither provision raises the investor’s ETF-share basis or cancels the original gain. A later share sale generally revives it.
BNY reported 77 individual-seeded US ETF launches holding about $16.6 billion through May 2026. Against ETFGI’s $15.78 trillion US market at end-June, that is approximately 0.105 per cent, rounded to 0.11 per cent. The niche matters to wealth managers, not yet to systemic market structure.
On 21 July 2026, Reuters reported that Treasury was examining potentially abusive sequences that contribute appreciated assets, then remove them through redemptions. No published rule or notice had prohibited the category by the 22 July cut-off. The fault line is factual: durable investment continuity versus a prearranged disposal programme.
Executive Summary
- Section 351 can reposition eligible diversified, low-basis portfolios into ETF shares without immediate federal gain recognition, but the embedded liability survives through carryover basis.
- In-kind redemptions can improve fund-level tax efficiency, yet they do not increase the investor’s basis or guarantee permanent tax avoidance.
- The strategy requires strict diversification, control, governance, sequencing and commercial durability, particularly after Treasury’s July 2026 warning on potentially abusive structures.
- Cross-border, estate, liquidity, fee and regulatory outcomes can materially alter the economics.
- For UHNW families, the structure is credible only when the investment rationale, governance and exit plan remain defensible without the tax benefit.
How a Section 351 ETF Conversion Works
Section 351 generally allows one or more persons to transfer property to a corporation solely for its stock without immediate gain recognition when the transferors control the corporation immediately afterwards. Section 368(c) defines control as at least 80 per cent of total voting power and at least 80 per cent of every other class of stock. Several contributors can form the control group if their transfers belong to one defined plan. Timing, subscription documents and the identity of each transferor therefore matter.
An ETF is usually treated as an investment company for this purpose, which introduces Section 351(e). The rule denies non-recognition when a transfer to an investment company produces prohibited diversification. Under the usual diversified-portfolio pathway, no issuer may represent more than 25 per cent of portfolio value and five or fewer issuers may not represent more than 50 per cent, subject to exclusions and look-through rules. This 25/50 screen tests whether the investor is bringing diversification into the fund rather than acquiring it through the exchange.
That is why the familiar founder-stock story often fails. An investor cannot generally contribute a single $50 million holding to a diversified ETF and claim that Section 351 itself created tax-deferred diversification. By contrast, a portfolio spread across 40 listed equities, with a 15 per cent largest position and 42 per cent in the five largest holdings, may fit the usual screen. Even then, eligibility is not automatic. Passing 25/50 is necessary in the standard pathway, not a complete tax opinion.
The denominator has its own traps. Cash and cash items are excluded for the statutory diversification test, so adding cash is not an automatic cure for an oversized security. Funds, derivatives, restricted securities, non-US assets and holdings with look-through issues require transaction-specific analysis. Market movement between testing and closing can also change the result. Prudent execution uses valuation timestamps and cushions rather than aiming at the legal boundary.
Consideration must generally be stock alone. Cash received by a contributor, other property or boot, assumed liabilities and side arrangements can alter recognition. The transfer also needs an orderly sequence that supports immediate control by the transferor group. A subsequent public subscription is not merely a distribution event if it was prearranged in a way that undermines the founding control facts. Separate tax, securities and fund-law analyses must therefore agree on the same chronology.
Legal ownership changes at closing. The ETF, through its custodian, owns the contributed securities. The founder owns ETF shares, not a personal sleeve inside the fund. The adviser and board govern the portfolio for all shareholders under the disclosed mandate. A founder may shape that mandate before launch but cannot retain personal dominion over which securities the ETF holds, sells or votes afterwards.
Basis preserves the tax account. Under Sections 358 and 362, the investor generally takes a carryover basis in the ETF shares and the fund generally takes a carryover basis in the contributed assets. Qualifying holding periods can tack under Section 1223. If a $50 million portfolio has a $10 million basis, the investor ordinarily begins with about $10 million of basis in the ETF shares, subject to transaction-specific adjustments. The $40 million gain is deferred, not forgiven.
Permanent records are part of the substance. The file should preserve eligible assets, tax lots, acquisition dates, valuations, corporate actions, contribution agreements, control-group evidence, board materials and the non-tax investment purpose. Hedges around launch can raise constructive-sale questions under Section 1259, while repurchases linked to loss harvesting can invoke Section 1091 wash-sale rules. Step transaction, substance over form and Section 7701(o) economic substance examine the whole plan. A genuine move into independent public-fund governance is materially different from stuffing unwanted appreciated securities into a vehicle for rapid extraction.
Inside the ETF In-Kind Redemption Engine
The founding exchange is only the first layer. Once listed, ordinary investors buy and sell ETF shares on an exchange. Those secondary-market trades do not normally move securities into or out of the fund. Authorised participants, usually large financial institutions, interact directly with the ETF in creation units. They deliver a basket for new ETF shares or surrender a large block of ETF shares for a redemption basket. Market makers help connect that primary process with public trading.
| Stage | Asset movement | Principal tax and governance point |
|---|---|---|
| Founding exchange | Eligible securities move to the ETF; contributors receive ETF shares | Section 351 may defer entry gain; control, diversification and carryover basis remain central |
| Secondary trading | Investors exchange ETF shares with one another | The fund’s portfolio does not change merely because its shares trade |
| In-kind redemption | The ETF distributes securities to an authorised participant | Section 852(b)(6) may prevent fund-level gain recognition |
| Portfolio transition | Compliant low-basis lots may leave in redemption baskets | Fund asset basis can improve, but the founder’s ETF-share basis does not rise |
For an in-kind redemption, the ETF distributes securities instead of selling them for cash. Section 852(b)(6) generally prevents a regulated investment company from recognising gain on property distributed to meet a redemption. If the adviser selects compliant low-basis tax lots for the basket, those embedded gains leave the fund without a fund-level taxable sale. Higher-basis assets remain, which can reduce the probability of future capital-gains distributions to continuing shareholders.
This is fund-level tax management, not a personal basis adjustment. The founder’s original gain remains embedded in the low basis of the ETF shares. The authorised participant that receives securities also bears trading economics. It prices hedging, spreads, market impact, custody, inventory and execution risk into the transaction. The cost can reach the fund, the transacting shareholder or market spreads according to the governing documents and market conditions. No redemption is economically costless.
Custom baskets add flexibility because they can differ from the ETF’s current pro rata portfolio. SEC Rule 6c-11 permits them only under written policies and procedures, detailed parameters, designated review, recordkeeping, best-interest controls and protections against inappropriate differential treatment among authorised participants. The board and adviser must manage conflicts, valuation, liquidity and cost allocation. Compliance with the rule does not determine whether the founding Section 351 exchange receives federal tax non-recognition.
Cash redemptions are less efficient when the fund must sell appreciated securities to raise money. Those sales can create taxable gains and market impact, while large founder exits can test authorised-participant capacity and secondary-market liquidity. Public listing offers daily tradability, but not guaranteed depth, tight spreads or permanent fund survival. A closure or liquidation can force a taxable outcome for shareholders who expected to hold indefinitely.
The fund must also remain a regulated investment company. Income, asset-diversification and distribution tests continue after launch. Custody, administration, accounting, transfer agency, exchange listing, distribution and market-making are continuing institutional functions, not launch formalities. The customised ETF tax strategy works only while the legal vehicle, investment mandate and operating ecosystem remain durable.
What the Tax Deferral Is Worth on a $50 Million Portfolio
The cleanest test is not whether deferral has value. It is whether that value exceeds the costs and improves on the investor’s real alternative. The illustrative model begins with a $50 million US equity portfolio, a $10 million historical basis and a $40 million unrealised gain across 40 stocks. It applies a simplified 31.8 per cent tax rate, comprising 20 per cent federal long-term capital gains, 3.8 per cent net investment income tax and an illustrative 8 per cent state tax.
An immediate sale creates $12.72 million of tax. After a $75,000 transition cost, only $37.205 million remains invested. The qualifying Section 351 route begins with $49.925 million of net asset value after the same transition cost and approximately $10 million of investor basis. The model assumes 7 per cent annual total return, split between 1.5 per cent dividends and 5.5 per cent price return. The retained or taxable portfolio costs 0.10 per cent annually; the customised ETF costs 0.30 per cent, plus a $500,000 establishment cost paid outside the fund.
| Strategy | Five-year after-tax liquidation value | Ten-year after-tax liquidation value |
|---|---|---|
| Immediate sale | $47.158 million | $60.745 million |
| Retain existing portfolio | $50.656 million | $68.916 million |
| Customised Section 351 ETF, before setup cost | $50.146 million | $67.615 million |
| Customised Section 351 ETF, after setup cost | $49.646 million | $67.115 million |
| Illustrative Section 721 exchange fund | Not presented | $64.195 million |
The ETF beats immediate liquidation by about $6.87 million after ten years before the setup cost because capital that would have gone to tax remains invested. Yet simple retention produces the highest liquidation value under identical returns because its annual fee is lower. Bancara’s analysis therefore separates wrapper deferral from investment alpha. The customised ETF needs a distinct portfolio, governance, succession or diversification rationale. Tax alone does not make a higher-cost fund superior to holding the same assets.
The Section 721 comparison assumes a 0.50 per cent entry cost, 0.85 per cent annual fee and the longer, often seven-year, partnership horizon associated with exchange funds. It is illustrative, not a universal provider quotation. At year ten, the customised ETF is worth $91.307 million before liquidation. Modelled terminal tax is $17.732 million at 23.8 per cent, $23.692 million at 31.8 per cent and $28.908 million at 38.8 per cent. If current Section 1014 applies at death, the model assumes no income tax on pre-death appreciation and a $91.307 million net value. That scenario excludes estate tax, state death taxes, statutory exceptions and future reform.
Customised ETF Versus Exchange Funds, SMAs and Direct Indexing
No capital-gains deferral strategy for UHNW investors should be judged without its counterfactual. A Section 721 exchange fund can pool concentrated positions and diversify through a partnership, but often brings a seven-year horizon, qualifying-asset exposure, higher fees and less liquidity. It can address a one-stock problem that the usual Section 351 pathway cannot, although partnership distributions and exit assets introduce different basis and portfolio risks.
| Route | Entry tax posture | Liquidity and control | Cost profile | Principal failure mode |
|---|---|---|---|---|
| Section 351 ETF | Conditional non-recognition for an eligible diversified portfolio | Daily trading, but fund owns assets and board governs | Setup cost plus recurring ETF fee | Failed qualification, closure or policy change |
| Section 721 exchange fund | Conditional partnership contribution treatment | Commonly long holding horizon and limited control | Entry and comparatively higher annual fees | Partnership, liquidity and distributed-asset risk |
| Direct indexing or tax-managed SMA | Security-level ownership and loss harvesting | High tax-lot and voting control | Advisory, trading and implementation costs | Appreciated sales during transition remain taxable |
| Outright taxable sale | Immediate gain recognition | Maximum reinvestment freedom | Tax plus execution cost | Permanent loss of capital to current tax |
| Credit, collar or prepaid forward | Liquidity or hedge, not wrapper conversion | Control constrained by collateral or contract | Interest, spread and counterparty charges | Margin call, constructive sale or forced disposal |
Direct indexing, tax-managed separately managed accounts and completion portfolios preserve security-level ownership. They can harvest losses, manage factor exposures and diversify future cash flows, but they cannot make an appreciated sale disappear during transition. Their value rises when the investor has losses, continuing contributions or a concentrated position that can be diluted over time.
Borrowing against securities can create liquidity without a current sale, but substitutes interest, collateral, covenant, margin-call and forced-sale risks for tax realisation. Collars and prepaid variable forwards can reduce exposure or monetise part of a position, subject to counterparty and constructive-sale analysis. A donor-advised fund, private foundation or charitable remainder trust can move gain outside the donor’s tax base under separate rules. It is charitable or split-interest capital, not retained family wealth.
Treasury Scrutiny Turns Sequencing Into the Central Risk
For each Section 351 ETF conversion, the 21 July 2026 Treasury warning shifts attention from the existence of each statute to the design of the entire transaction. Reuters identified officials Kevin Salinger and Erika Nijenhuis as studying strategies in which Section 351 contributions and ETF redemptions could dispose of appreciated founder assets and replace them with an intended portfolio. At the evidence cut-off, that scrutiny was a reported warning, not formal product-specific guidance and not a declaration that every customised ETF conversion is abusive.
Settled law and transaction interpretation must remain separate. Section 351, the investment-company exception, carryover-basis rules, Section 852(b)(6) and Rule 6c-11 are real. A tax opinion may conclude that a particular exchange should qualify, but it is not an IRS ruling. The more the documents, trading plan and launch timetable suggest an integrated rapid purge, the harder it becomes to treat the contribution, listing and redemptions as independent events.
Step-transaction doctrine can combine formally separate steps when they are mutually interdependent or prearranged. Substance-over-form analysis tests whether the legal wrapper matches the economic result. Section 7701(o) asks, where relevant, whether the transaction meaningfully changes the taxpayer’s economic position apart from federal income-tax effects and whether there is a substantial non-tax purpose. Deliberately adding securities only so they can be extracted, sometimes described as stuffing, intensifies those questions.
Evidence of durability cuts the other way. A written investment reason for changing manager, governance or portfolio; independent board oversight; third-party investors; a strategy that the founder would accept before tax; and no obligation to remove named securities can support the continuity case. None is a universal safe harbour. The inquiry remains sensitive to facts, sequencing, communications and subsequent conduct.
A 2021 Senate Finance discussion draft proposed narrowing regulated investment companies’ non-recognition on in-kind redemptions, but it was not enacted. Future reform could instead be targeted at seasoning periods, founder-linked baskets, transaction disclosure, low-basis stuffing or unusually large contributions. That route could preserve routine ETF creation and redemption while constraining bespoke extraction.
Broad reform would travel much further. Restricting Section 852(b)(6) across the industry could increase fund sales, capital-gains distributions and trading friction for ordinary ETF holders. Reforming Section 1014 would affect appreciated assets far beyond ETFs and could replace basis adjustment at death with carryover basis or deemed realisation. Investors cannot assume retroactivity, grandfathering or legislative passage in either direction.
The practical exposure includes audits, information requests, transaction disclosure, penalties where positions lack adequate authority or disclosure, and reputational risk. The phrase tax dodge is a journalistic description, not a legal classification. Legality, statutory purpose, distributional equity and revenue impact require separate analysis. No authoritative revenue estimate isolating customised Section 351 ETFs had been identified by the research cut-off.
A Small Tax Niche With a Large Wealth-Management Addressable Market
The $16.6 billion individual-seeded pool reported by BNY is about 0.11 per cent of $15.78 trillion in US ETF assets. FactSet separately placed the market near $15.7 trillion at end-June 2026, while ICI reported $15.60 trillion for May. Different dates and methods preclude false precision.
BNY’s 77 reported launches through May 2026 compare with ETFGI’s 1,033 US ETF launches and 190 closures during 2025. Barron’s separately reported 39 funds and $8.7 billion of seed assets from 2021 through 2025. Different periods and methodologies make these evidence of activity, not a clean growth series.
Disclosed products show a wide commercial range. Cambria’s USEW launched on 18 December 2025 with a 0.25 per cent management fee and 0.05 per cent in acquired-fund fees, or 0.30 per cent total. Reuters reported a $1.8 billion Eagle Capital SMA-to-ETF conversion in March 2024 through Goldman Sachs ETF Accelerator, with a 0.80 per cent management fee. Barron’s reported that standalone structures can be uneconomic below roughly $30 million. That is a commercial observation, not a statutory minimum or tax safe harbour.
The broader asset pool is substantial. Cerulli reported $13.7 trillion in managed accounts for 2024. Morningstar reported more than $500 billion in tax-managed SMAs, up 67 per cent from 2022. These accounts contain the tax lots, reporting history and investor relationships that can feed wrapper conversions. Growth in active ETFs, reported by ETFGI at $2.49 trillion globally at end-May 2026, strengthens the distribution case for differentiated mandates.
A launch needs an adviser or sponsor, fund series or trust, board, counsel, administrator, accountant, transfer agent, custodian, exchange, distributor, market maker and authorised participant. Syndicated launches can lower contribution size, but add control-group, allocation, conflict, qualification and cost-sharing complexity. Recurring fees strengthen the need for independent governance.
Market consequences remain localised. More custom baskets may increase specialist authorised-participant work, hedging demand and transition trading. Large exits may widen spreads or create market impact in less liquid holdings. Securities moving from personal accounts to funds also move proxy voting authority to advisers. Yet evidence does not establish price distortion across US equities. The immediate competitive effect is in private banks, advisers, ETF platforms and tax practices. Systemic claims remain unproven.
Commercial durability is the overlooked underwriting issue. Seed assets do not guarantee third-party distribution, deep liquidity or sponsor commitment. A fund that cannot cover operating costs may merge or close, crystallising gains for a founder whose strategy depended on indefinite holding. Families must examine sponsor capital, break-even assets, authorised-participant depth, spread history, closure protocol and whether the investment mandate can attract investors beyond the original contributor.
Why the US Tax Result Travels Poorly
The federal architecture is not a global passport. US citizens and resident aliens generally remain subject to US tax on worldwide income while living abroad. Their state position can be equally consequential because residence, domicile and departure rules differ. A Section 351 ETF conversion that works federally may still face state tax, reporting or sourcing questions, especially when the family moves before, during or after launch.
Non-US investors confront a different perimeter. US-source dividends can face withholding, often subject to treaty relief. US-situs assets can also create estate-tax filing exposure. IRS guidance identifies a $60,000 threshold for certain non-resident estates, but treaties, ownership structures, domicile and asset character can change the outcome. A low threshold is a reason for analysis, not a universal tax bill.
Home-country law may treat the in-specie contribution of securities to a US fund as a taxable disposal even when the United States grants non-recognition. In the United Kingdom, offshore-fund reporting status affects whether gains on disposal can receive capital treatment, while investors may also need to account for excess reportable income. HMRC’s reporting-fund list is fund and share-class specific. Status must be verified rather than inferred from an ETF’s US registration.
European Union retail access can be restricted where a US ETF lacks a PRIIPs key information document. This is a distribution barrier, not a tax ruling, but it can constrain liquidity and eligible ownership for European families. Trusts, holding companies and private banks can add their own classification and suitability layers.
Australia generally treats an in-specie transfer of shares or units as a capital-gains tax event unless a specific rollover applies. The US Section 351 result should therefore not be assumed to prevent Australian recognition. Switzerland can exempt private capital gains for an individual treated as a private investor, but professional-securities-dealer classification can alter the treatment. Cantonal facts and the investor’s conduct remain important.
FATCA and the OECD Common Reporting Standard reinforce transparency across custodians and jurisdictions. They do not make the strategy unavailable, but they make the relevant accounts, ownership and income reportable within their respective regimes. For a cross-border family, the correct unit of analysis is the investor, trust, holding structure, fund, custody chain and estate plan together.
A Six-Gate Family-Office Decision Framework
Suitability begins with the portfolio. The strongest candidate has a large, diversified, low-basis taxable account, a long horizon, limited liquidity needs, a genuine reason to change mandate or governance, and tolerance for public-fund control. A single-stock founder, short-horizon seller, control-sensitive shareholder or family with uncertain residency may face more complexity than benefit.
Break-even depends on the counterfactual. Deferral can beat an immediate sale, while lower-cost retention may beat the ETF. A different exposure, governance result or succession objective must justify the fee. Losses, charitable gifts, future contributions and state residence can change the comparison.
The investment committee record can be organised around six gates:
- Investment purpose: Document why the family wants a different strategy, manager, diversification pattern or governance structure independent of tax.
- Portfolio eligibility: Test every security and tax lot, the 25/50 thresholds, valuation timing, control group, asset restrictions and sufficient cushions for market movement.
- Whole-plan tax analysis: Review contribution, launch subscriptions, expected portfolio transition, hedges, redemptions, borrowing, charitable plans and the estate endpoint as one sequence.
- Fund governance: Examine adviser independence, board oversight, Rule 6c-11 basket controls, conflicts, cost allocation, valuation, liquidity and proxy voting.
- Commercial durability: Underwrite sponsor capital, break-even assets, distribution, authorised-participant capacity, spreads, closure, merger and liquidation procedures.
- Policy stress: Model targeted restrictions, a broader change to Section 852(b)(6), higher capital-gains rates, loss of Section 1014 basis adjustment and an early need for cash.
Independent tax counsel should assess qualification and reporting; securities counsel should address fund formation; investment advisers should test purpose and alternatives; basis specialists should validate tax lots; and estate advisers should analyse ownership transfers. Custody and execution experts examine transition capacity. Cross-border families add home-country tax, trust and treaty review.
Warning signs include calling the structure tax-free, promising immunity from Treasury challenge, treating one concentrated holding as automatically eligible, omitting carryover basis, or presenting fund-level lot removal as a founder basis increase. Missing closure plans, undisclosed transition costs, no valuation cushion and expected founder control after launch deserve equal scepticism.
Exit choice determines whether deferral survives. Selling low-basis ETF shares generally recognises gain. Borrowing adds financing risk. Charity removes the asset from retained family ownership. Under current Section 1014, qualifying inherited shares may receive fair-value basis at death, but estate tax, state death tax, exceptions and future reform remain separate. Each endpoint needs stress testing.
The Wrapper Works Only When the Investment Case Survives
The proven result is narrow. A qualifying Section 351 ETF conversion can move an eligible, diversified, low-basis portfolio into public fund shares without immediate federal gain recognition. Carryover basis preserves the liability. Section 852(b)(6) can help the fund remove appreciated assets through in-kind redemptions without fund-level gain, but it does not erase the shareholder’s gain.
Durability depends on purpose, eligibility, sequencing, independent governance, commercial survival and exit. The structure is strongest when the investment policy would make sense before tax and the family accepts a genuine transfer of control. It is weakest when contribution and redemption look like one engineered disposal.
Four signals now deserve sustained attention: Treasury or IRS guidance on founder-linked transitions; transaction disclosures, examinations and enforcement signals; launch, liquidity and closure data across the bespoke ETF cohort; and legislative proposals affecting Section 852(b)(6) or Section 1014. The 21 July warning does not settle the law, but it raises the documentation standard.
For wealthy investors asking how to diversify appreciated stock without selling, the answer remains conditional.
A bespoke ETF for wealthy investors can be a legitimate continuity mechanism.
It is not guaranteed tax freedom, hidden ownership or investment alpha.
The wrapper works only when its investment case, governance and documented substance survive scrutiny on their own.
FAQ entries
1. What is a Section 351 ETF conversion?
A Section 351 ETF conversion is a conditional exchange in which one or more investors contribute property to a corporation, such as an ETF, solely for stock while meeting an immediate 80 per cent control test. If all requirements apply, federal gain is not recognised at entry. Carryover basis preserves the embedded gain in the investor’s ETF shares and in the fund’s contributed assets.
2. Can a wealthy investor contribute one concentrated stock to a customised ETF tax-free?
Not through the usual diversified-portfolio pathway. Section 351(e) can deny non-recognition when a transfer to an investment company creates prohibited diversification. The common screen allows no issuer above 25 per cent and no five or fewer issuers above 50 per cent, subject to exclusions and look-through rules. A single founder stock generally fails because the exchange itself creates diversification.
3. Does a Section 351 ETF erase capital gains?
No. A qualifying exchange defers recognition rather than erasing gain. The investor generally receives ETF shares with carryover basis, while the ETF carries over the basis of the contributed securities. Selling low-basis ETF shares usually revives the deferred liability. A potential basis adjustment at death or a completed charitable transfer operates under separate law and has distinct estate, ownership and policy consequences.
4. How do ETF in-kind redemptions improve tax efficiency?
An authorised participant can surrender a creation unit and receive securities rather than cash. Section 852(b)(6) generally prevents a regulated investment company from recognising gain on property distributed to satisfy a redemption. Selecting compliant low-basis lots can improve the basis profile of assets left in the fund and reduce future capital-gains distributions. It does not increase the founder’s basis in ETF shares.
5. What is the 25/50 diversification test for a Section 351 ETF?
Under the usual pathway, no single issuer may exceed 25 per cent of portfolio value and five or fewer issuers may not exceed 50 per cent, after specified exclusions and any required look-through analysis. Cash and cash items are excluded from the relevant asset denominator, so cash is not an automatic cure. Passing 25/50 is necessary in the usual case but is not a complete tax opinion.
6. What did Treasury say about customised Section 351 ETFs in July 2026?
Reuters reported on 21 July 2026 that Treasury officials were studying potentially abusive strategies, including structures that contribute appreciated securities and use redemptions to remove them in favour of an intended portfolio. As of 22 July, no published regulation, revenue ruling or notice had prohibited customised Section 351 ETF launches as a class. Purpose, sequencing and documentation remain central.
7. How does a customised ETF compare with a Section 721 exchange fund?
A customised Section 351 ETF generally requires an already diversified eligible portfolio and offers public trading, subject to fund governance, fees and qualification risk. A Section 721 exchange fund can address concentrated positions through a partnership, but often involves a seven-year horizon, higher fees, qualifying-asset exposure and different distribution risks. The correct comparison depends on tax basis, control, liquidity, duration and investment purpose.
8. What does the $50 million case study show?
The illustrative investor has a $50 million portfolio, $10 million basis and $40 million unrealised gain. At a 31.8 per cent combined rate, immediate tax is $12.72 million. After ten years, the customised ETF exceeds immediate liquidation because more capital remains invested, but trails simple retention under identical returns because its annual fee is higher. The model demonstrates deferral value, not tax alpha.
9. Can a non-US investor rely on the US Section 351 result?
No universal conclusion is available. A home country may treat an in-specie contribution as a taxable disposal even when the United States grants non-recognition. Non-US holders may also face US dividend withholding, estate-tax exposure, local fund classification, PRIIPs access barriers or trust rules. UK, EU, Swiss and Australian treatment differs, while FATCA and CRS make relevant accounts and income reportable.
10. Which family offices may be suited to a Section 351 ETF conversion?
The strongest profile is a family with a large, already diversified, low-basis taxable account, a long investment horizon, limited near-term liquidity needs, a genuine reason to change mandate or governance, and tolerance for public-fund control and policy scrutiny. A concentrated-stock owner, short-horizon seller, control-sensitive shareholder or cross-border family with uncertain residence may find the structure unsuitable or disproportionately complex.
Works Cited
- 26 USC Sections 351, 358 and 362
- 26 CFR Section 1.351-1
- 26 USC Section 852
- SEC Rule 6c-11 Adopting Release
- US Treasury flags Wall Street tax strategies as potentially abusive
- Section 351 conversions and the ETF opportunity
- US ETF assets reach $15.78 trillion
- 26 USC Section 1014
- US citizens and resident aliens abroad
- Approved offshore reporting funds