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Adrian Briner, Tobias StieglerMay 28, 2026 – A5 Ed. 2/2026

Swiss holding company and German specialists: taxes, social security and permanent establishment risk

International
Entreprises

The intra-group deployment of specialized personnel between Switzerland and Germany raises complex tax and social security issues. Drawing on a comprehensive real-world example, this article analyzes six typical scenarios—ranging from a simple service contract to a CEO working from home in the border region. It examines the implications of recent legal changes: the new domestic legal basis for senior executives (Art. 5(1)(a bis) DBG), the revised double taxation treaty between Switzerland and Germany, and the 2025 OECD Model Commentary on the home office as a permanent establishment.

Sophia Ritzmann, Petrit Ismajli, Michael Grebe, Olga-Vasiliki PlousiouApril 30, 2026 – A4 Ed. 2/2026

Impact of MiKaDiv reporting in Germany on Swiss custodians

International
Individuals

The reporting procedure for capital gains tax on dividends (MiKaDiv) marks a turning point in Germany’s withholding tax landscape. Starting February 1, 2027, paying agents must submit electronic reports to the Federal Central Tax Office—a requirement that has significant implications for Swiss and other foreign custodians. This article analyzes the new obligations, the information requirements throughout the custody chain, and the consequences of incomplete data reporting for the market position of Swiss custodians.

Jan SeltmannApril 1, 2026 – A3 Ed. 2/2026

Reclassification of profit distributions as relevant salary

Social Security
Reforms

Employee shareholders are often caught off guard by social security authorities when a distributed dividend is subject to social security contributions in whole or in part because it is reclassified as taxable income. This article outlines current practice and its limitations, arguments against reclassification, and possible future developments.

Bernhard Schopper, Petrit IsmajliFebruary 26, 2026 – A2 Ed. 1/2026

Should Swiss Financial Institutions Take Part in the EU “FASTER”-Directive?

International
Reforms

The EU directive on Faster and Safer Tax Relief of Excess Withholding Taxes (FASTER) was formally approved at the end of 2024. The purpose of the directive is to make the refund procedure of withholding tax in the EU more efficient for investors and more secure for tax authorities. Member States will have to transpose the directive into national legislation by 31 December 2028 and these rules will become applicable from 1 January 2030. But what are the implications for Swiss-based financial institutions (FI)?

Thomas Hug, Daniela Martinis-Arth February 26, 2026 – A1 Ed. 1/2026

Need to adapt practice for intercantonal and international home office locations

Entreprises
International

In late 2025, the OECD published an update to the OECD Model Tax Convention, which sets out in detail the conditions under which working from home can constitute a permanent establishment. The OECD introduces a new concept of the company’s deemed control over employees’ homes. Based on the legal framework and existing Federal Supreme Court case law, this article analyzes whether Swiss practice regarding the home office as a permanent establishment should be adjusted in light of this new concept and the experience gained from several years of remote work.

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June 2, 2026

Corporate tax law 2026

Entreprises
Individuals

Everything current and important about corporate tax law on over 700 pages: Case studies, detailed solutions and all slides on the relevant issues. Here you will find all documents of the ISIS seminar "Corporate Tax Law 2026" according to the following content description.

Thomas Jaussi, Markus KüpferJune 2, 2026

Updates on withholding tax and stamp duties (2026)

Entreprises

Withholding tax and stamp duties repeatedly raise challenging questions in practice - particularly with regard to the recognition of capital contribution reserves, non-cash benefits in a group relationship and the tax treatment of fiduciary relationships. Using practical case studies, Thomas Jaussi and Markus Küpfer show which requirements must be met for a tax-free distribution from capital contribution reserves in accordance with Art. 5 para. 1bis of the Swiss Federal Tax Act (VStG), when a refund of turnover tax is possible following a change in FTA practice and how non-cash benefits are to be assessed in the case of an intra-group sale of a shareholding. The solutions provide you with the necessary tools to recognize and correctly assess typical stumbling blocks in withholding tax and stamp duties.

René Matteotti, Philipp BetschartJune 2, 2026

Current cases on intercantonal and international corporate tax law (2026)

International
Entreprises

The determination of tax domicile and the delimitation of permanent establishments are among the most challenging issues in intercantonal and international corporate tax law - especially in constellations with home offices, cross-border infrastructures or competing cantonal tax jurisdictions. Using practical case studies, Philipp Betschart and René Matteotti show how the place of effective management is to be determined, when home office activities constitute a permanent establishment and how profits are to be separated internationally according to the Authorized OECD Approach. The importance of sovereign rulings in the assessment procedure and revision claims in the case of intercantonal double taxation are also dealt with. The solutions provide you with the necessary tools to confidently assess jurisdiction and separation issues and to recognize tax risks at an early stage.

Susanne Schreiber, Toni HessJune 2, 2026

Tax law challenges for sole proprietorships and partnerships (2026)

Individuals
Entreprises

In practice, partnerships raise numerous tax law issues - from the distinction between private and business assets to property gains in the monistic and dualistic system and succession constellations with prior-year losses. Using practical case studies, Susanne Schreiber and Toni Hess show how self-employment, business asset qualification and the taxation of copyrights are to be assessed for tax purposes. The solutions provide you with the necessary tools to recognize typical stumbling blocks for partnerships and to structure them correctly for tax purposes.

Oliver Jäggi, Remo KüttelJune 2, 2026

Current problems of taxation of stock corporations and shareholders (2026)

Entreprises
Individuals

The tax treatment of employee shares, the application of minimum taxation (Pillar II) and the valuation of securities and participations in the balance sheet raise complex demarcation issues in practice - particularly in the light of recent Federal Supreme Court rulings. Based on practical case studies, Oliver Jäggi and Remo Küttel show how treasury shares are to be treated for profit tax purposes when sold to employees, which Swiss group company is considered a business unit subject to supplementary tax and under which conditions value fluctuation reserves and value adjustments on participations are recognized for tax purposes. It also deals with the calculation of property gains tax in the case of hidden capital contributions among majority shareholders. The solutions provide you with the necessary tools to implement current developments in profit tax, Pillar II and real estate gains tax in practice.

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Recent Webinars

Oliver Werneyer, Sven Steger, Jan ReinhardtMay 28, 2026

AI in Tax Law – Practical Deepening

Other

Artificial intelligence is fundamentally changing tax and fiduciary practice - knowing the technical basics is a prerequisite for its targeted use. This webinar provides a practical insight into how data interfaces (APIs, MCP) and corporate LLM work and uses two specific products to show what AI can do for compliance and tax advice today. Benefit from live demonstrations and an up-to-date overview of market developments.

Iliriana Dreni, Daniel de Vries ReilinghMarch 26, 2026

Plans Fantômes

Entreprises

Discover phantom stock plans, a flexible and strategic tool for remunerating and retaining key employees, without changing the capital structure. This webinar (in French) gives you a clear, practical overview of how they work and their tax treatment.

Hanna Brozzo, Marlene KobierskiMarch 12, 2026

Lump-sum Taxation

International
Entreprises

Lump-sum taxation is a key instrument of Swiss tax law for internationally mobile private individuals - and at the same time politically and practically challenging. This webinar (in german) will provide you with a compact overview of how it works, current developments and typical challenges. Benefit from practical insights and concrete case studies.

Kathrin Egli Arginelli, Robert Desax, Luzius CaveltiMarch 5, 2026

Case law, Practice and Legislation (1/2026)

Entreprises
International

The recording of the webinar (in german) gives you a compact overview of the most important developments in tax law, available at your preferred time. In the 90-minute session, the speakers will highlight current rulings, new legal provisions and practical trends. Well-founded, precise and practical, so that you can keep your specialist knowledge up to date and react to legal changes at an early stage.

Julien Latour, Cedric PanchaudFebruary 5, 2026

Employee stock option plans

Entreprises
Individuals

Replay this webinar (in french). The speakers discuss employee share-based incentive plans and their tax implications, illustrated by concrete examples.

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Open Access: In-depth contributions on tax law topics – available free of charge.

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Case examples with detailed solution guidance and slides from ISIS seminar workshops. Materials can be purchased per seminar or as individual workshops.

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Recordings of selected ISIS webinars. Upon purchase, you get immediate access to the video of the desired presentation.

Topic Areas

The zsis) contributions are divided into nine tax law topic areas. The topics are marked with corresponding colors.

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Online magazine for tax law

Current Articles

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Tricky Case Studies

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Recent Webinars

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Tricky Case Studies

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Current Articles