Patent Box in Switzerland: How It Works & Eligibility

The patent box is one of several special tax topics relevant to companies with intellectual property in Switzerland. Switzerland’s patent box regime reduces the tax on income from qualifying intellectual property by up to 90 per cent at the cantonal level. Introduced on 1 January 2020 as part of the TRAF reform, the regime replaced the internationally criticised cantonal IP privilege and now follows the OECD modified nexus approach. For companies that own patents and conduct their own R&D, the effective cantonal tax on patent income in low-rate cantons can fall below 2 per cent.

This guide explains how the patent box works, which IP qualifies, the nexus calculation, cantonal differences, how to combine it with the R&D super-deduction, and the step-by-step process for claiming. For the broader tax framework, see our guide to corporate tax in Switzerland.

What is the patent box and how much tax does it save?

The patent box is a cantonal tax regime that allows companies to exclude a substantial portion of their net income from qualifying intellectual property from the cantonal and municipal tax base. The maximum exclusion is 90 per cent, meaning only 10 per cent of qualifying IP income is taxed at the cantonal level.

The regime exists at the cantonal level only. The federal corporate income tax of 8.5 per cent (effectively 7.83 per cent) continues to apply in full to all income, including patent income. This is a critical distinction: the patent box does not eliminate Swiss tax on IP income; it reduces the cantonal and municipal component.

Before TRAF, several cantons offered privileged tax regimes for holding companies, domiciliary companies, and mixed companies. These old regimes were abolished on 31 December 2019 because they did not comply with international standards set by the EU and OECD. The patent box, together with the R&D super-deduction, replaced them as internationally accepted alternatives.

The patent box is voluntary. Companies must actively elect to apply it, substantiate their eligibility, and perform the required calculations. It does not apply automatically to all patent-owning companies.

What is the legal basis for the Swiss patent box?

The patent box was enacted through the Federal Act on Tax Reform and AHV Financing (Bundesgesetz ueber die Steuerreform und die AHV-Finanzierung, STAF, commonly referred to as TRAF). Swiss voters approved the act in a referendum on 19 May 2019, and it entered into force on 1 January 2020.

The federal framework is set out in the Tax Harmonisation Act (Steuerharmonisierungsgesetz, StHG):

• StHG Art. 24a defines the patent box regime, including qualifying IP, the nexus approach, and the maximum 90 per cent relief.
• StHG Art. 24b governs the R&D super-deduction.
• StHG Art. 24d addresses the step-up of hidden reserves upon entry into the patent box or into Swiss tax jurisdiction.
• StHG Art. 25b sets the overall relief limitation at 70 per cent of pre-adjustment taxable profit.

The StHG provides the framework, but each canton enacts its own implementing legislation. This produces variation in the practical application, particularly regarding the relief percentage (some cantons apply less than the maximum 90 per cent) and the administrative requirements for qualifying.

The full text of the StHG is available on Fedlex.

Which intellectual property qualifies for the patent box?

The patent box applies only to IP that confers a legally protected exclusive right. Not all forms of intellectual property qualify.

Qualifying IP

• Patents granted in Switzerland or abroad (the right must be in force, not merely applied for)
• Supplementary protection certificates (ergaenzende Schutzzertifikate) — these extend patent protection for pharmaceutical and plant protection products beyond the standard 20-year patent term
• Plant variety rights
• Topographies of semiconductor products
• Comparable foreign rights that provide exclusivity functionally equivalent to a Swiss patent, as assessed by the competent cantonal tax authority

Non-Qualifying IP

• Trade marks — protected under trade mark law, not patent law; they do not confer exclusivity over a technical innovation
• Copyrights — protect expression, not functional inventions; software copyrights in particular do not qualify
• Trade secrets and know-how — no legal exclusivity; unprotectable by definition
• Designs — registered designs protect appearance, not technical function

There is one nuance regarding bundled IP. Where a patent is licensed together with associated trade marks, know-how, or copyrights as part of an integrated licence, cantonal practice generally allows the entire licence income to be included in the patent box, provided the patent is the dominant element. If the non-qualifying IP contributes more than an ancillary share of the licence value, a split allocation is required.

Software is a recurring question. Switzerland does not grant patents on computer programs as such (unlike the United States). However, software embedded in a patented technical process, or protected by a patent granted in a foreign jurisdiction that Switzerland recognises as comparable, may qualify. Pure software protected only by copyright does not.

How does the modified nexus approach affect eligibility?

Switzerland adopted the OECD/G20 modified nexus approach (BEPS Action 5) as the basis for calculating patent box eligibility. The nexus approach ensures that the tax benefit is proportional to the actual R&D activity performed by the taxpayer itself.

How the Nexus Fraction Works

The nexus fraction determines what share of qualifying IP income is eligible for the patent box. It is calculated as follows:

Nexus fraction = (Qualifying R&D expenditure x 1.3) / Total R&D expenditure

Where:

• Qualifying R&D expenditure includes R&D performed by the taxpayer’s own employees and R&D outsourced to unrelated third parties
• Total R&D expenditure includes all R&D related to the qualifying IP, including R&D outsourced to related parties (group companies)
• The 1.3 uplift (30 per cent mark-up) on qualifying expenditure is permitted under the OECD rules and ensures that companies with modest related-party outsourcing are not penalised disproportionately
• The fraction is capped at 1.0 (100 per cent)

Practical Effect

A company that conducts all its R&D in-house achieves a nexus fraction of 1.0, and 100 per cent of its qualifying IP income enters the patent box.

A company that outsources 40 per cent of its R&D to a sister company abroad achieves a lower nexus fraction. Say total R&D is CHF 10 million, of which CHF 6 million is in-house and CHF 4 million is outsourced to a related party. The qualifying expenditure is CHF 6 million x 1.3 = CHF 7.8 million. The nexus fraction is CHF 7.8 million / CHF 10 million = 0.78. Only 78 per cent of the qualifying IP income benefits from the patent box.

This design incentivises companies to locate their R&D functions in Switzerland alongside their IP ownership — a deliberate policy outcome.

R&D Outsourced to Unrelated Third Parties

R&D outsourced to universities, research institutes, or unrelated commercial contractors counts as qualifying expenditure, the same as in-house R&D. This distinction between related and unrelated outsourcing is central to the nexus calculation.

How is the patent box relief calculated?

Once the qualifying IP income and the nexus fraction are established, the patent box relief is calculated in three steps:

Step 1: Determine Net IP Income

Net IP income is the gross income from qualifying IP minus directly attributable costs. Attributable costs include:

• R&D expenses related to the qualifying IP
• Amortisation of the IP (if acquired)
• A share of overhead costs allocable to the IP function
• A notional charge for the use of routine functions (arms-length return on routine activities)

The objective is to isolate the residual profit attributable to the qualifying IP, excluding routine returns on manufacturing, distribution, and administrative functions.

Step 2: Apply the Nexus Fraction

Multiply the net IP income by the nexus fraction. The result is the eligible patent box income.

Step 3: Apply the Cantonal Relief Percentage

Each canton sets a relief percentage, up to the maximum of 90 per cent permitted by StHG Art. 24a. The eligible patent box income is multiplied by the relief percentage, and that amount is excluded from the cantonal tax base.

Formula:

Cantonal tax base reduction = Net IP income x Nexus fraction x Cantonal relief percentage

How does patent box implementation differ between cantons?

All cantons have implemented the patent box, but the relief percentage and practical requirements differ. The following table compares implementation in selected cantons that are particularly relevant for IP-intensive companies.

Notes: Effective rates on patent income are approximate and assume maximum nexus fraction (1.0), 90 per cent cantonal relief, and domicile in the cantonal capital. The federal rate of 7.83 per cent is included in all figures. Actual rates depend on the specific commune and any municipal multiplier adjustments. For standard corporate tax rates without patent box, see our tax rates by canton guide.

The variation in effective patent box rates is primarily driven by the underlying cantonal rate, since all major cantons apply the maximum 90 per cent relief. In the lowest tax cantons, the patent box produces effective rates below 10 per cent on qualifying income.

Can you combine the patent box with the R&D super-deduction?

Yes. The patent box is only one element of the TRAF toolbox. The other key instrument is the R&D super-deduction (StHG Art. 24b), which allows cantons to grant a deduction of up to 150 per cent of qualifying R&D expenditure against taxable income.

How the R&D Super-Deduction Works

Under this provision, a company that spends CHF 1 million on qualifying R&D in Switzerland can deduct up to CHF 1.5 million from its cantonal tax base. The additional 50 per cent represents the “super” component — it is a deduction for R&D that was never an actual expense.

Qualifying R&D expenditure for the super-deduction includes:

• Personnel costs of employees directly engaged in R&D (wages, social security, pension contributions)
• A flat-rate mark-up of 35 per cent on personnel costs to cover R&D overhead (materials, equipment depreciation, premises)
• Costs of R&D outsourced to third parties in Switzerland (up to 80 per cent of the invoiced amount)

R&D conducted abroad does not qualify for the super-deduction, even if it qualifies for the nexus fraction. This reinforces the incentive to locate R&D activities in Switzerland.

The 70 Per Cent Relief Cap

StHG Art. 25b imposes an overall limit: the combined tax reduction from the patent box, the R&D super-deduction, and any step-up depreciation may not exceed 70 per cent of the company’s taxable profit before these adjustments.

This cap prevents a company with large patent income and heavy R&D expenditure from reducing its cantonal tax to zero. At least 30 per cent of pre-adjustment profit remains fully taxable.

In practice, the cap binds most frequently for companies that have both significant patent box income and substantial R&D super-deduction claims. For companies using only one of the two instruments, the cap rarely comes into play.

What does a patent box calculation look like in practice?

Consider a Swiss biotech company domiciled in Zug with the following profile:

Step 1: Nexus Fraction

Qualifying R&D expenditure: CHF 1,600,000 (in-house) x 1.3 = CHF 2,080,000, capped at total R&D of CHF 2,000,000, so nexus fraction = 1.0.

Step 2: Eligible Patent Box Income

CHF 2,500,000 x 1.0 = CHF 2,500,000.

Step 3: Patent Box Deduction (Zug, 90% Relief)

CHF 2,500,000 x 90% = CHF 2,250,000 excluded from cantonal tax base.

Step 4: R&D Super-Deduction

Swiss R&D personnel costs: CHF 1,200,000 x 1.35 (overhead mark-up) = CHF 1,620,000 qualifying base. Super-deduction (50% additional): CHF 1,620,000 x 50% = CHF 810,000.

Step 5: Check the 70% Cap

Total reductions: CHF 2,250,000 + CHF 810,000 = CHF 3,060,000. 70% of pre-adjustment profit: CHF 5,000,000 x 70% = CHF 3,500,000. The reductions (CHF 3,060,000) are below the cap, so both apply in full.

Step 6: Taxable Income for Cantonal Purposes

CHF 5,000,000 - CHF 2,250,000 (patent box) - CHF 810,000 (R&D super-deduction) = CHF 1,940,000.

Step 7: Tax Liability

Effective rate: CHF 470,458 / CHF 5,000,000 = 9.41%, compared to approximately 11.9 per cent without the patent box and R&D super-deduction. The saving is over CHF 124,000 per year on CHF 5 million in profit.

Which industries benefit most from the patent box?

The patent box is not industry-specific, but the requirement for qualifying IP means it disproportionately benefits sectors with heavy patenting activity:

• Pharmaceuticals — extensive patent portfolios covering active ingredients, formulations, and delivery methods. Supplementary protection certificates extend coverage beyond the standard 20-year patent term, keeping income in the patent box longer.
• Biotechnology — gene therapies, diagnostic methods, and biomanufacturing processes are routinely patented. Basel and the Lake Geneva region host major clusters.
• Medtech — medical devices, surgical instruments, and implants are patent-dense. Switzerland is a global medtech hub, particularly around Bern, Basel, and the Zurich region.
• Engineering and precision manufacturing — patents on mechanical innovations, materials science, and process technology. Strong representation in Zurich, Central Switzerland, and the Mittelland.
• Cleantech and energy — patents on solar technology, battery systems, and environmental processes. Growing sector in Vaud and Zurich.
• Software — only where the software is protected by a patent (rare in Switzerland). Companies relying solely on copyright protection cannot use the patent box.

Companies in these sectors that conduct their R&D predominantly in Switzerland and hold their own patents benefit most, because their nexus fraction is high and their qualifying IP income is substantial.

How do you claim the patent box step by step?

1. Identify qualifying IP. Review your patent portfolio and determine which patents, supplementary protection certificates, or comparable rights are in force. Expired, abandoned, or pending-only patents do not qualify.

2. Isolate net IP income. Separate the income attributable to qualifying IP from routine business income. This requires a functional analysis that identifies the value contributed by the patent versus manufacturing, distribution, and administrative functions. Many companies use a residual profit split method.

3. Calculate the nexus fraction. Compile all R&D expenditure related to the qualifying IP and classify it as own R&D, unrelated-party outsourcing, or related-party outsourcing. Apply the formula with the 1.3 uplift.

4. Determine the cantonal relief percentage. Confirm the relief percentage applicable in your canton of domicile. While most cantons apply 90 per cent, verify the current cantonal legislation.

5. Apply the 70 per cent cap. If you also claim the R&D super-deduction or step-up depreciation, calculate the combined reduction and verify it does not exceed 70 per cent of pre-adjustment taxable profit.

6. Obtain a tax ruling (recommended). Apply to the cantonal tax authority for an advance ruling confirming the eligibility of your IP, the allocation method, and the expected relief. A ruling provides certainty and avoids disputes during the assessment process. Ruling requests are typically processed within four to eight weeks and are free of charge.

7. File the patent box claim with the tax return. Include the patent box calculation as an appendix to the cantonal corporate tax return. Attach supporting documentation: patent registrations, licence agreements, R&D cost allocation, nexus fraction calculation, and the advance ruling (if obtained).

8. Maintain documentation. Keep contemporaneous records of all R&D expenditure, IP income allocation, and nexus calculations. The cantonal tax authority may review the claim during the assessment or in a subsequent audit.

For companies entering the patent box for the first time, StHG Art. 24d permits a step-up: the difference between the book value and the fair market value of qualifying IP at the time of entry can be amortised over the following years, reducing the tax base during the transition period.

Why you can trust this guide

Patent box rules cited here are based on the Tax Harmonisation Act (StHG Art. 24a-24d), the Federal Act on Tax Reform and AHV Financing (STAF/TRAF), and the OECD/G20 BEPS Action 5 modified nexus approach. Cantonal relief percentages and effective rates reflect 2026 data from cantonal tax authority publications. The worked example uses standard calculation methodology consistent with the Swiss Tax Conference’s published guidance on patent box implementation.

Frequently Asked Questions

Does the patent box apply to federal tax in Switzerland?

No. The patent box is a purely cantonal measure. The federal corporate income tax rate of 8.5 per cent (effectively 7.83 per cent) applies in full to all income, including income from qualifying intellectual property. The relief operates only at the cantonal and municipal level, where cantons may exempt up to 90 per cent of net patent income from their tax base. This means that even with maximum patent box relief, the federal component remains payable.

Can software companies use the Swiss patent box?

Only if the software is protected by a patent or a comparable right that confers legal exclusivity. Switzerland does not grant patents on software as such, unlike the United States. However, software that is embedded in a patented technical process or device, or that is protected by a patent in a recognised foreign jurisdiction, may qualify. Copyrights alone do not qualify for the patent box. In practice, most pure software companies cannot benefit from this regime unless they hold specific patents covering their technology.

What is the maximum combined tax relief under the patent box and R&D super-deduction?

StHG Art. 25b caps the total tax reduction from all special regimes — patent box, R&D super-deduction, and step-up depreciation — at 70 per cent of taxable profit before these adjustments. This means that regardless of how large the qualifying patent income or R&D expenditure is, at least 30 per cent of the company's pre-adjustment profit remains subject to full cantonal and municipal taxation. The cap prevents situations where a company with significant IP and R&D could otherwise reduce its cantonal tax burden to near zero.

How does the modified nexus approach affect outsourced R&D?

Under the OECD modified nexus approach adopted by Switzerland, only R&D expenditure incurred by the taxpayer itself or by unrelated third parties generates full nexus credit. R&D outsourced to related parties (group companies) counts only partially. If a company outsources 50 per cent of its qualifying R&D to a sister company, the nexus fraction is reduced, and consequently the share of patent income eligible for the patent box decreases. The rule is designed to ensure that the tax benefit flows to the jurisdiction where the actual research takes place.

How is the patent box relief calculated in practice?

The relief is calculated as a percentage of net qualifying IP income multiplied by the nexus fraction. Net IP income is gross qualifying income minus all attributable costs, including amortisation of the IP, direct R&D costs, financing costs, and overhead allocation. The nexus fraction is qualifying R&D expenditure incurred by the company itself divided by total acquisition and development costs for the IP. For a company that conducted all R&D internally, the nexus fraction is 1.0, and up to 90% of the net IP income can be excluded from the cantonal tax base.

Which Swiss cantons have implemented the patent box and are there differences?

All 26 Swiss cantons are required to offer the patent box under the federal Tax Harmonisation Act (StHG Art. 24a). However, cantons have discretion in setting the exact exemption percentage up to the 90% maximum. Most cantons implement the full 90% maximum relief. Some cantons have combined the patent box with higher overall tax rates, meaning the effective tax on qualifying IP income varies. In Zug, a company applying maximum patent box relief could reduce effective cantonal tax on qualifying IP income to below 1.5%.

Can the patent box be claimed on IP acquired from a third party?

Yes, but with an important limitation. If a company acquires a patent from an unrelated third party, the acquisition cost generates qualifying R&D expenditure (at 70% under the OECD uplift). However, the nexus fraction for acquired IP is typically lower than for self-developed IP because the acquisition cost alone, without subsequent development, does not generate the same level of nexus credit as internal R&D. Further development of the acquired patent by the company itself increases the nexus fraction over time. Acquired IP from related parties does not generate qualifying nexus expenditure.

Does the patent box apply to royalty income received from licences?

Yes. Royalties and licensing fees received from third parties for the use of qualifying IP are the primary form of qualifying patent box income. The net royalty income — after deducting directly attributable costs — is eligible for the up-to-90% exemption, subject to the nexus fraction. Capital gains on the sale of qualifying IP are also eligible for the patent box in most cantons. The income must arise from a qualifying right as defined in StHG Art. 24a; royalties from trade marks, software copyrights, or know-how alone do not qualify.

What documentation is required to claim the Swiss patent box?

A company claiming the patent box must maintain documentation covering: a list of all qualifying IP with registration numbers or equivalent, the nexus calculation showing qualifying R&D expenditure by IP asset, the income allocation showing which revenue streams are attributable to each IP asset, a cost allocation methodology allocating direct and indirect costs to each asset, and evidence that the IP is used in income-generating activities. The cantonal tax authority reviews the patent box claim as part of the annual tax return process. Inadequate documentation may result in denial of the relief or a reduced exemption.

Legal references: Tax Harmonisation Act (StHG), Federal Act on Tax Reform and AHV Financing (STAF/TRAF), Federal Direct Tax Act (DBG). Cantonal rates and relief percentages reflect 2026 data from cantonal tax authorities. This guide is for informational purposes and does not constitute tax advice. For company-specific guidance, consult a qualified adviser.