Sale of shares in a real estate-preponderant company (SPI): valuation and notarial deed

Since 27 June 2026, selling SPI shares requires a notarial deed.

Introduction: since 27 June 2026, selling shares in a real estate company is no longer casual

How much is a company really worth when it owns, for the most part, only walls? And since when do you need a notary to sell its shares? These two questions, long treated lightly, now arise with new intensity. A real estate-preponderant company, or SPI, is an unlisted company whose assets consist mainly of buildings or property rights. Selling its shares is economically equivalent to selling real estate, yet the legal mechanics and the valuation mechanics follow their own rules, which many owners discover too late. The law has, moreover, just tightened the applicable formalities.

« The sale of shares in a real estate-preponderant company is recorded, on pain of nullity, by an authenticated deed, by a lawyer-countersigned deed or by a chartered accountant deed. », article 1865-1 of the French Civil Code, introduced by Law no. 2026-534 of 25 June 2026.

Three factors converge in 2026 to make this a first-order issue. First, the new formality, applicable since 27 June 2026, turns a simple signature between the parties into a solemn deed whose absence renders the sale null and void. Second, the taxation of these sales remains heavy, with 5% registration duties and no allowance, which makes the stated price decisive. Third, the valuation of these companies, based on the revalued net asset value and on a set of discounts, leaves a margin of appreciation that the tax authority and the buyer both know how to challenge. This article details the tax definition of the SPI, the predominance test, the new formality, the valuation methods, the applicable discounts, the taxation, the France and Switzerland comparison, then two figured case studies, before a set of frequently asked questions and a summary.

Secure the sale of your real estate shares

Before going further, if you are preparing the sale or acquisition of shares in a company holding real estate, an upfront framing avoids unpleasant surprises on price and on form.

You can book thirty minutes with Hectelion to secure both the valuation of your shares and the compliance of the transaction with the new regime. Our team works on transactions from 2 to 500 MCHF, in France and in Switzerland, in full independence from traditional financial intermediaries.

Acontos: estimate your company's value online for free

Before diving into the detail, note that Hectelion has developed Acontos, an online tool for audit, due diligence and business valuation, powered by Claude Sonnet 5 artificial intelligence by Anthropic and calibrated by Hectelion's methodology. From your accounts, it produces a first estimate of the value of your shares in a few minutes, free of charge and without keeping any document.

Launch the valuation simulator to obtain an order of magnitude, then read on to understand the drivers behind it.

Definition: what is a real estate-preponderant company?

For tax purposes, article 726 of the French General Tax Code defines the real estate-preponderant company as the legal entity, whatever its nationality, whose shares are not traded on a regulated market and whose assets are, or were during the year preceding the sale, mainly made up of buildings or property rights located in France, or of shares in other companies that are themselves real estate-preponderant. The word "mainly" refers to a threshold of more than 50% of the real value of the assets. In practice, a private real estate company, a holding company that owns a rental portfolio, or an operating company whose value rests mostly on its walls can all fall into this category. The legal form matters little, whether it is a French SCI, a limited liability company, a simplified joint-stock company or an unlisted public limited company. What counts is the real economic composition of the fixed assets, not their accounting entry.

Two neighbouring notions must be distinguished. Real estate predominance in the tax sense determines the regime of registration duties and capital gains. The new formality of the Civil Code, for its part, targets the sale of shares in those same companies. The two regimes overlap widely but are not identical, and a transaction may fall under one without the practitioner spontaneously thinking of the other. That is precisely where mistakes hide.

Origin: from the private real estate company to the 2026 anti-fraud tightening

For decades, the private real estate company has been the favoured vehicle for holding and passing on family real estate wealth, valued for its flexibility and for the ease with which its shares could change hands. A simple private deed was enough, often drafted without a third party, sometimes without even a serious valuation of the shares. This simplicity built the success of the real estate family holding company, but it also opened the door to opaque structures, undervaluations and hard-to-trace sales. The legislator has progressively tightened the grip, first through taxation, with specific registration duties, then through formality.

Law no. 2026-534 of 25 June 2026, on the fight against social and tax fraud, published in the Official Journal of 26 June 2026, marks a turning point. By inserting article 1865-1 into the Civil Code, it ends the era of the private deed for these sales. The stated objective is twofold, to strengthen the legal security of transactions and to contribute to the fight against money laundering and terrorist financing, by systematically interposing a legal or accounting professional.

The real estate predominance test: how to know if your company is concerned

The test is conducted by comparing, at real value rather than book value, the fraction of the assets made up of buildings with the total value of the assets. If buildings and property rights represent more than half of those assets, the company is deemed real estate-preponderant. Two subtleties deserve the greatest attention. First, the assessment is made not only at the date of the sale, but also during the preceding year, which prevents artificially de-immobilising the balance sheet on the eve of the transaction. Second, and this is an often ignored point, buildings assigned by the company to its own industrial, commercial, agricultural or professional operations are excluded from the calculation.

This exclusion changes everything. An industrial small business that owns its factory, a hotel that operates its own walls, a clinic that occupies its building are, in principle, not real estate-preponderant companies, because those buildings serve the operations. Conversely, a company that lets the same building to third parties falls into the category. The boundary is therefore economic and not cadastral. Determining on which side a target sits is a due diligence step in its own right, because it governs both the tax cost and the mandatory form of the deed.

The new formality since 27 June 2026: notarial deed, lawyer deed or chartered accountant deed

Since 27 June 2026, the sale of shares in a real estate-preponderant company is valid only if it is recorded by one of three exhaustively listed deeds, an authenticated deed received by a notary, a deed countersigned by a lawyer within the meaning of article 1374 of the Civil Code, or a chartered accountant deed established in the extension of an ongoing engagement. The sanction is radical, it is absolute nullity. A sale carried out by a simple private deed is void of effect, the tax authority refuses to register it, and the transaction must be redone in the proper form. For a buyer, this is a major legal risk, because ownership of the shares is not validly transferred.

This tightening has immediate practical consequences. The timetable of a transaction must factor in the intervention time of the chosen professional and the verification of the origin of funds under anti-money-laundering obligations. The cost of the deed adds to the tax cost. Above all, the intervention of a professional third party makes an approximate valuation of the shares all the more visible and challengeable. It therefore becomes essential to have, upfront, a solid and documented valuation, able to withstand the scrutiny of the notary, the lawyer, the chartered accountant and, ultimately, the tax authority.

Why value shares in an SPI rigorously

Valuing the shares of a real estate-preponderant company with method answers five concrete motivations. First, the stated price serves as the base for the 5% registration duties, so that a poorly supported value exposes the parties to a reassessment if the tax authority retains a higher market value. Second, in a family transfer, an undervaluation may be recharacterised as a disguised gift, with a claw-back of duties and penalties. Third, between shareholders, a poorly founded price feeds litigation, notably when a minority shareholder exits. Fourth, the buyer wants to measure precisely what is being bought, in particular the latent tax taken over with the company. Fifth, the professional now required for the deed expects a credible valuation support.

Valuation is therefore not a theoretical exercise. It protects the seller against reassessment, the buyer against overpayment, and both parties against nullity or recharacterisation. It forms the documentary foundation of the transaction, on the same footing as the deed itself.

The valuation methods for a real estate-preponderant company

The valuation literature, from the guide of the French Directorate General of Public Finance on the valuation of companies and unlisted securities to the international IVS standards, by way of the RICS Red Book and the French real estate valuation charter, converges on one principle. A real estate-preponderant company is not an operating company, its value rests on its assets and not on a recurring operating result. Asset-based and real estate methods therefore prevail, while methods designed for industrial or service companies play a secondary, even unsuitable, role. Six approaches deserve to be reviewed, each with its domain of relevance.

The first two are asset-based. Accounting net assets are only a starting point, since buildings are carried at their depreciated historical cost, far below their market value. Revalued net assets, also called mathematical value, are on the contrary the reference method, reconstructing the market value of the buildings, restating the rest of the balance sheet, then deducting debt and latent tax. The guide of the Directorate General of Public Finance clearly states that, for holding companies and real estate-preponderant companies, mathematical value prevails, weighted where appropriate. Revalued net assets therefore form the foundation of any SPI valuation.

The third and fourth belong to the income approach, but they must be carefully distinguished. For a real estate company, the relevant income is that of rents, capitalised at a market yield or discounted through a cash flow applied to real estate, following the capitalisation and discounting approach used by the valuation charter, by the RICS and by IVS 400. In contrast, the enterprise cash flow based on EBITDA and the weighted average cost of capital, like the capitalisation of an operating result, only make sense if the company genuinely runs a business, a hotel or a clinic for example. A private real estate company with pure holding has no operating EBITDA, so applying an enterprise cash flow to it would be a misconception. For an operating company that is real estate-preponderant, the two are combined instead, the income value of the operations and the substantial value of the walls, following a mixed method close to the practitioners' method used in Switzerland.

The fifth and sixth belong to the market approach. Comparable transaction multiples are only useful in their real estate form, namely prices per square metre and capitalisation rates observed on similar buildings, which feed directly into the market value retained in the revalued net assets. Company transaction multiples, drawn from sales of operating companies, are not suitable for an asset-based SPI. As for stock market multiples, the only relevant listed comparables are listed property companies, which are valued at a discount or premium to their net asset value, following the framework of the European Public Real Estate Association, and not according to an industrial EBITDA multiple. For a small unlisted real estate company, these listed comparables remain delicate to handle, given the differences in size, liquidity and diversification, and call for large discounts. Ultimately, revalued net assets remain central, corroborated by real estate income and real estate comparables, while enterprise cash flow and stock market multiples concern only the operating layer of an operating company. A robust valuation crosses these approaches, explains their weighting and retains a defensible central value, consistent with IVSC standards.

How the revalued net asset value is built, step by step

The reference method is that of the revalued net asset value, or RNAV. It unfolds in five steps. First, the market value of each building held is established, from an independent real estate appraisal based on rents, market yields and comparable transactions. Second, the rest of the balance sheet is restated at its real value, cash, receivables, shareholder current accounts, provisions and off-balance-sheet commitments. Third, all debt is deducted, foremost the mortgage debt, to obtain a gross revalued net asset value. Fourth, latent tax is taken into account, that is the tax that would be due if the company sold its buildings at their market value, since the buyer of the shares takes over this embryonic charge. Fifth, the discounts specific to unlisted securities are applied.

This asset-based approach differs clearly from valuation by flows or by operating multiples, which are relevant for a company generating a recurring operating result. When the company operates its own walls, a mixed reading is required, crossing the income value of the operations with the substantial value of the real estate. The valuer's role is precisely to choose the right weighting and to document each assumption. This rigour echoes the logic of separating real estate assets from operating assets that we deployed in a restructuring mandate.

The applicable discounts: illiquidity, minority and latent tax

The value of shares in an unlisted real estate company is almost never equal to its pro rata share of revalued net assets. Three discounts adjust it, and their handling makes all the difference between a defensible valuation and a challengeable figure. The illiquidity discount reflects the difficulty of quickly selling securities for which there is no organised market, a buyer is not found in a day and the exit is uncertain. The minority discount applies when the block sold does not confer control, because a minority shareholder decides neither on the sale of the buildings nor on the distribution of results. The latent tax discount, finally, captures the tax the company carries on the real estate capital gain not yet realised.

These discounts do not add up mechanically and must be justified case by case, according to the shareholder structure, the nature of the buildings and the holding horizon. An excessive discount weakens the seller before the tax authority, an insufficient discount harms the buyer. Our publication on premiums and discounts in business valuation details the usual ranges and the conditions for applying them. The aim is not to stack allowances, but to faithfully reflect the economic reality of the interest sold.

Income tax or corporate tax: a major impact on the value of the shares

The tax regime of the real estate company directly influences the value of its shares, and this is a parameter too often overlooked. In a private real estate company subject to income tax, said to be semi-transparent, the building is not depreciated for tax purposes and the shareholders are taxed each year on property income. On resale, the capital gain falls under the individuals' regime, with holding-period allowances leading to an income tax exemption after twenty-two years and a social levies exemption after thirty years. The latent tax taken over by the buyer of the shares is then relatively moderate, and decreases with the holding period.

In a company subject to corporate tax, the logic is reversed. The building is depreciated, its net book value falls each year, and the capital gain on sale, computed as the difference between the price and this net book value, incorporates the recapture of depreciation. It is taxed at the corporate tax rate, with no holding-period allowance. The latent tax lodged in the company is therefore far heavier, which justifies a higher latent tax discount. For an identical building, the shares of a company subject to corporate tax are often worth less than those of a company subject to income tax. Identifying the applicable regime is therefore a prerequisite to any valuation.

The taxation of the sale: 5% registration duties and capital gains

The sale of securities in a real estate-preponderant company bears a registration duty of 5% of the sale price, with no allowance at all, whether the securities are shares or partnership interests. This rate contrasts with the ordinary regime of share sales, taxed at 0.1%, and of ordinary partnership interest sales, taxed at 3% after allowance. The tax base is the sale price, increased by any charges borne by the buyer, or the real market value if it is higher than the declared price. This mechanism gives the tax authority a direct control lever, which reinforces the requirement for a solid valuation.

To this duty is added, for the seller, the taxation of the capital gain on the sale of securities, computed on the difference between the sale price and the acquisition price of the shares. Depending on the seller's situation, individual or legal entity, and depending on the holding period, the regime differs significantly. The combination of registration duties, capital gains and, now, the cost of the mandatory deed can represent a significant share of the price. Anticipating this overall charge, and articulating it with the valuation, is an integral part of a serious preparation of the transaction.

Real estate-preponderant companies and the real estate wealth tax

Holding real estate through a company does not allow escaping the real estate wealth tax. The shares of a real estate-preponderant company enter the IFI base in proportion to the fraction of their value representing the buildings held, directly or indirectly. The taxpayer must therefore estimate the market value of the shares, then apply the company's real estate coefficient. This annual valuation echoes the logic retained in a sale, market value of the buildings, restatement of the balance sheet and account taken of debt, except that the tax authority tightly frames the deductibility of certain debts, notably shareholder current accounts and intragroup loans.

Two points call for vigilance. On the one hand, buildings assigned to an operating activity may, under conditions, qualify as business assets and leave the base, hence the importance of the nature of the building, already decisive for the predominance test. On the other hand, the usual sale discounts, illiquidity and minority, are admitted more restrictively for wealth tax purposes, and must be handled with care. A valuation that is consistent from one year to the next, aligned between the wealth tax return and the value retained in the event of a sale, significantly reduces the risk of a challenge.

France and Switzerland: French SPI and Swiss economic transfer

The subject does not stop at the French border, and the comparison with Switzerland sheds light on the logics at play. In France, the regime now combines a strict deed formality with 5% registration duties. In Switzerland, there is no obligation for a notarial deed for the sale of shares in a public limited company, but a powerful tax mechanism targets the same type of transaction. Article 12, paragraph 2, letter a of the Federal Act on the Harmonisation of Direct Taxes treats as a transfer of real estate the transfer of a majority interest in a real estate company held in the taxpayer's private wealth. Economically, whoever acquires the majority of the shares acquires the power to dispose of the buildings, and the transaction is therefore subject to the real estate gains tax.

This notion of economic transfer, known in German as wirtschaftliche Handänderung, is accompanied in several cantons by transfer duties. The Swiss seller escapes the French notarial formality, but cannot ignore the cantonal real estate gains tax nor the need for a rigorous asset-based valuation. The two systems converge on the substance, selling the securities of a real estate company amounts to selling the building, and tax law ensures that the corporate wrapper does not let the transaction escape taxation. We detail these gaps in our analysis of the differences in business sales between France and Switzerland, and in our study of holding companies in Switzerland.

Valuing dismembered real estate company shares: usufruct and bare ownership

The transfer of real estate wealth frequently goes through the dismemberment of the shares of the private real estate company, the donor passing bare ownership to their children while keeping the usufruct, and therefore the income, for life. The question then arises of the respective value of the usufruct and the bare ownership. For tax purposes, article 669 of the French General Tax Code sets a scale according to the age of the usufructuary, used to settle gift duties. This scale is simple, but it does not always reflect the economic reality, in particular for an asset that strongly generates income.

An economic approach, based on discounting the future income received by the usufructuary, usefully complements the scale when the aim is to objectify a split between shareholders or to secure a large transaction. The valuation of dismembered shares thus crosses two levels, the value of the shares in full ownership, established by the revalued net assets and the discounts, then the split key between usufruct and bare ownership. The new deed formality also applies to these sales and gifts of dismembered shares, which reinforces the need for a documented valuation.

When to use an independent valuation

Several situations make an independent valuation of the shares not merely useful, but essential. In a sale to a third party, it sets a defensible negotiation price and documents the market value expected by the tax authority. In a family transfer, by gift or by inheritance, it guards against the risk of a disguised gift and secures the base of the duties. On the exit or entry of a shareholder, it objectifies the value of the block concerned and prevents conflicts. In a reorganisation, contribution, merger or asset spin-off, it establishes fair ratios. Finally, in a tax audit, it is the best line of defence.

The common thread of these situations is the existence of a third party whose interests diverge, buyer, co-shareholder, heir or tax authority. Faced with them, a value asserted without method carries no weight. An independent valuation, built according to IVSC standards and backed by a real estate appraisal, carries on the contrary all its evidentiary weight.

Buy-side due diligence before acquiring shares in an SPI

Acquiring the shares of a real estate-preponderant company is not merely buying a building, it is taking over a company with all of its liabilities, known or latent. A simple real estate appraisal is therefore not enough, and financial and legal due diligence is required. It covers title deeds and their origin, the strength of ongoing leases and rental income, technical diagnostics and energy performance, the planning situation, easements, mortgages and security interests encumbering the buildings. It also examines debt, shareholder current accounts, any litigation and the tax and social compliance of the company.

This review governs the price as much as the security of the transaction. A fragile lease, a hidden debt, a planning non-compliance or an underestimated latent capital gain significantly change the value of the shares and the risk borne by the buyer. Due diligence feeds directly into the negotiation, by justifying price adjustments, specific warranties or an escrow clause. For the buyer as for the seller, it turns an opaque transaction into a traceable and defensible operation.

Who to turn to

The choice of valuer rests on three criteria. The first is dual competence, both in financial valuation and in an understanding of real estate, because valuing an SPI requires dialogue with the real estate appraiser while mastering balance sheet restatements, latent tax and discounts. The second is independence, the only guarantee of a value that is credible in the eyes of a third party, which excludes participants in a conflict of interest on the transaction. The third is mastery of the Franco-Swiss framework, essential as soon as an asset, a shareholder or a project straddles the border.

Hectelion meets these three criteria. An independent boutique firm, endowed with dual Franco-Swiss expertise and economic independence from traditional financial intermediaries, it conducts valuations aligned with IVSC standards and with AMF and SIX market practice. Our team combines business valuation and financial due diligence to deliver an enforceable valuation file, ready to be presented to the notary, the lawyer or the tax authority.

Advantages: legal security, defensible price, controlled taxation

A rigorous valuation of the shares of a real estate-preponderant company provides three major advantages. The first is legal security, because a solid valuation file, combined with a deed compliant with the new formality, shields the transaction from nullity and challenge. The second is a defensible price, both in the negotiation with the buyer and before the tax authority, which finds before it a supported market value rather than a bare figure. The third is controlled taxation, since anticipating the 5% registration duties, the capital gain and the latent tax allows structuring the transaction without unpleasant surprises.

To these benefits is added a relational advantage. A family transfer prepared on clear foundations preserves peace among heirs, where an arbitrary value feeds resentment. The seriousness of the approach protects both the wealth and the bonds.

Limits: subjectivity of the appraisal, narrow market, tax uncertainty

The approach also has its limits, which must be acknowledged to better frame them. The first lies in the share of subjectivity of the real estate appraisal, two appraisers can retain significantly different market values depending on the yields and comparables chosen, and this variability feeds directly into the revalued net assets. The second lies in the narrowness of the market for unlisted shares, which makes the illiquidity discount hard to calibrate and the exit value uncertain. The third lies in tax uncertainty, since the tax authority may retain a market value higher than the declared price and challenge the discounts applied.

These limits do not condemn the method, they impose prudence and documentation. Retaining median assumptions, crossing several appraisals, justifying each discount and preserving the traceability of sources are as many safeguards. A valuation that is lucid about its own margins of uncertainty is more robust than a value displayed with false precision.

The 5 mistakes to avoid

Mistake 1: ignoring the new formality and signing a private deed

Since 27 June 2026, a sale of SPI shares by a simple private signature is null and void. The most serious mistake is to conclude the transaction as before, without an authenticated deed, without a lawyer deed or a chartered accountant deed. The tax authority refuses registration, ownership of the shares is not transferred, and the transaction must be entirely redone. Checking the SPI qualification upfront and retaining the right form of deed is the first reflex to acquire.

Mistake 2: confusing book value and market value of the buildings

Many value the shares from the accounting balance sheet, where buildings often appear at their depreciated historical cost, far below their market value. This approach underestimates the revalued net assets and exposes to a reassessment. The valuation must start from a real estate appraisal at market value, never from net book value alone.

Mistake 3: neglecting the latent tax taken over by the buyer

The buyer of the shares inherits the latent real estate capital gain lodged in the company, and therefore the tax that will one day strike it. Omitting this charge leads to overvaluing the securities and harming the buyer. The latent tax discount must be quantified and integrated into the value, according to the gap between market value and book value of the buildings.

Mistake 4: applying unjustified flat-rate discounts

Mechanically stacking an illiquidity discount, a minority discount and a latent tax discount, without documenting them, weakens the valuation. The tax authority easily challenges standardised allowances. Each discount must be calibrated against the shareholder structure, the nature of the buildings and the holding horizon.

Mistake 5: forgetting the predominance test over the preceding year

Real estate predominance is assessed at the date of the sale but also during the preceding year. Attempting to de-immobilise the balance sheet on the eve of the transaction to escape the regime is ineffective and risky. The qualification must be analysed over time, taking into account the exclusion of buildings assigned to operations.

Case 1: sale of a French private holding company owning a let office building

A family holds, through a French private holding company, an office building entirely let to third parties. As the building is let and not assigned to its own operations, the company is indeed a real estate-preponderant company. The independent appraisal retains a market value of 6.0 M EUR. The residual mortgage debt amounts to 2.2 M EUR, so that the gross revalued net asset value comes out at 3.8 M EUR. The latent capital gain, the difference between the market value and the historical book value of the building, justifies a latent tax discount of 0.3 M EUR, bringing the base to 3.5 M EUR. An illiquidity discount of 10%, reflecting the absence of an organised market for these shares, leads to a value of the securities of 3.15 M EUR for 100% of the capital.

On this basis, the 5% registration duties represent 157,500 EUR, borne by the buyer. The sale must imperatively be recorded by an authenticated deed, by a lawyer deed or by a chartered accountant deed, on pain of nullity. This file illustrates the articulation of real estate appraisal, balance sheet restatement, justified discounts and taxation, each link having to be documented to withstand the double scrutiny of the professional drafting the deed and of the tax authority. A value displayed without this chain of evidence would have exposed the family to a reassessment on the base of the duties.

Case 2: sale of the majority of a Geneva real estate company

A shareholder sells all the shares of a Geneva real estate company owning a rental building, within the management of their private wealth. The building is appraised at 12.0 MCHF and the mortgage debt reaches 5.0 MCHF, for a revalued net asset value of 7.0 MCHF. A latent tax discount of 0.6 MCHF, for the latent reserves on the building, brings the base to 6.4 MCHF, and an illiquidity discount of 8% leads to a value of the shares of about 5.89 MCHF. No notarial deed is required for this sale of shares, unlike in France.

By contrast, the transfer of the majority of the shares constitutes an economic transfer within the meaning of article 12 of the Federal Act on the Harmonisation of Direct Taxes. The transaction is therefore subject to the cantonal real estate gains tax. For illustration, with an investment value of 8.0 MCHF, the real estate gain comes out at 4.0 MCHF, and a real estate gains tax of about 10%, for a long holding period, would represent about 0.4 MCHF, to which cantonal transfer duties may be added. This case shows that the absence of a notarial formality does not mean an absence of constraints, cantonal real estate taxation and the requirement of an asset-based valuation remaining fully present.

A word from the director

« In the sale of real estate shares, the most frequent mistake is not to be off by a few points on a discount, it is to treat the transaction as a mere formality among insiders. The building is visible, the value of the company much less so. »

« The new 2026 formality has one merit, it forces a professional into the loop, and therefore a valuation that stands up. What was tolerated yesterday no longer is. We see this constraint as an opportunity to better protect our clients. »

« Our conviction is simple, a share in a real estate company is never mechanically worth its pro rata share of assets. It is worth what an informed buyer is willing to pay, once latent tax, illiquidity and the real power attached to the block sold have been weighed. Our job is to establish this price and to make it enforceable. »‍

Aristide Ruot, Founder and Managing Director of Hectelion.

FAQ: the 10 essential questions on the sale of SPI shares

Introduction: what to remember before the questions

The questions below gather the most frequent concerns of directors, family shareholders and buyers facing the sale of shares in a real estate-preponderant company. They cover qualification, formality, valuation and taxation, in France and in Switzerland. The answers are deliberately concise and do not replace personalised advice.

Q1: What is a real estate-preponderant company?

It is an unlisted company whose assets are, at the date of the sale or during the preceding year, made up of more than 50% in real value of buildings or property rights, excluding buildings assigned to its own operations. The legal form, SCI, limited liability company, simplified joint-stock company or public limited company, is indifferent, only the economic composition of the assets counts.

Q2: Since when is a notarial deed required to sell SPI shares?

Since 27 June 2026, pursuant to Law no. 2026-534 of 25 June 2026 and the new article 1865-1 of the Civil Code. The sale must be recorded by an authenticated notarial deed, by a lawyer deed or by a chartered accountant deed, on pain of nullity.

Q3: What happens if the sale is signed by private deed?

It is struck by absolute nullity. The tax authority refuses its registration, the transfer of ownership of the shares is not validly carried out, and the transaction must be redone in the legal form. The risk weighs in particular on the buyer, who believes they hold securities they do not hold.

Q4: How are the shares of a real estate company valued?

By the revalued net asset value method, which starts from the market value of the buildings from an appraisal, restates the rest of the balance sheet, deducts debt, takes latent tax into account, then applies the discounts specific to unlisted securities. When the company operates its own walls, a mixed approach crosses income value and substantial value.

Q5: What discounts can be applied?

Mainly an illiquidity discount, a minority discount if the block sold does not confer control, and a latent tax discount for the unrealised real estate capital gain. These discounts must be justified case by case and do not add up mechanically.

Q6: What is the rate of the registration duties?

The sale of SPI securities bears a registration duty of 5% of the sale price, with no allowance, whether the securities are shares or partnership interests. The base is the sale price, or the real market value if it is higher.

Q7: Who pays the registration duties, the seller or the buyer?

The registration duties are in principle borne by the buyer, unless otherwise agreed between the parties. The seller, for their part, is taxed on the capital gain on the sale of the securities. The allocation of costs is often the subject of a negotiation.

Q8: Is a company that operates its own walls an SPI?

In principle no, because buildings assigned to its own industrial, commercial, agricultural or professional operations are excluded from the predominance test. A small business that owns and operates its factory or its hotel is therefore generally not an SPI, unlike a company that lets the same building to third parties.

Q9: How does Switzerland treat the sale of a real estate company?

Switzerland does not require a notarial deed for a sale of shares, but article 12 of the Federal Act on the Harmonisation of Direct Taxes treats the transfer of a majority interest in a real estate company as a transfer of real estate, subject to the cantonal real estate gains tax, sometimes accompanied by transfer duties.

Q10: Why call on an independent valuer?

Because the value of the shares serves as a tax base, a negotiation basis and evidence before a third party whose interests diverge. An independent valuer produces an enforceable file, aligned with IVSC standards, able to withstand the scrutiny of the notary, the lawyer or the tax authority, and to secure both the price and the form of the transaction.

Estimate your company's value with Acontos, Hectelion's online simulator

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Conclusion: value fairly and sell in due form, the twofold requirement of 2026

The sale of shares in a real estate-preponderant company now combines two inseparable requirements, a fair valuation and an irreproachable form. The first rests on the revalued net asset value, on a serious real estate appraisal and on controlled discounts. The second flows from the new article 1865-1 of the Civil Code, which since 27 June 2026 requires an authenticated deed, a lawyer deed or a chartered accountant deed, on pain of nullity. Neglecting either exposes the transaction to reassessment or nullity. Treating them together, upfront, secures both the wealth and the transaction.

Article summary

A real estate-preponderant company is an unlisted company whose assets are made up of more than 50% of buildings at real value, excluding buildings assigned to its own operations. Since 27 June 2026, the sale of its shares requires an authenticated notarial deed, a lawyer deed or a chartered accountant deed, on pain of nullity, pursuant to Law no. 2026-534 of 25 June 2026. For tax purposes, these sales bear a registration duty of 5% with no allowance, to which is added the taxation of the capital gain for the seller.

Valuation rests on the revalued net asset value method, which starts from the market value of the buildings, restates the balance sheet, deducts debt and applies three discounts, illiquidity, minority and latent tax, calibrated case by case. The two case studies, a French private holding company at 3.15 M EUR and a Geneva real estate company at 5.89 MCHF, illustrate the articulation of real estate appraisal, restatements, discounts and taxation, in France and in Switzerland.

In Switzerland, the absence of a notarial formality does not exempt from the real estate gains tax, triggered by the economic transfer on the transfer of a majority interest. In both jurisdictions, the logic is identical, selling the securities of a real estate company amounts to selling the building, and the law ensures that both the valuation and the taxation are treated with rigour. An independent and documented valuation file is the best guarantee of a safe transaction.