What we speak on
Taxation of crypto assets, the holding period debate, DAC 8 and reporting, voluntary disclosure, tax audits with crypto, and the proceedings we run ourselves.
Since 1989
Background · publications · press
Matthias Steger
German certified tax advisor in Potsdam, near Berlin. Trained first as a mainframe programmer, then as a tax official, then nine years auditing companies for the tax authorities — and since 2021 working on crypto assets exclusively. Each of those stages does real work in a crypto case.
In short
- Certified as a Steuerberater in 2009; own firm since 2006.
- Nine years as a tax auditor, plus six as IT officer for the audit division.
- Expert witness before the Finance Committee of the German Bundestag, October 2025.
- Author with Erich Schmidt Verlag and DATEV; five own proceedings before the tax courts.
- Vice-President of the Berlin-Brandenburg tax advisers association.
Career
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1989 – 1992
Trained as a programmer
At the Fiducia mainframe data centre, on the systems banks used to process bulk data. A thorough schooling in handling large, structured datasets.
Languages: mainframe assembler · C++ · Pascal · Turbo Basic · dBase · COBOL
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1992 – 1994
Degree in public finance
University of Applied Sciences for Administration and Justice, graduating as Diplom-Finanzwirt. The move from technology into the tax administration.
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1995 – 2001
Degree in business administration
University of Hagen, studied alongside full-time work in the tax administration. Graduated as Diplom-Kaufmann.
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1997 – 2003
IT officer for the audit division
Berlin-Charlottenburg tax office. Responsible among other things for introducing the IDEA audit software, migrating workstations to MS Office and contributing to the BP 2000 project.
IDEA remains the software German tax auditors use to analyse datasets today.
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1997 – 2006
Tax auditor
Nine years auditing companies of varying size across many sectors. That period still shapes how the practice works in defence work: we know the questions before they are asked.
One year longer and the tax adviser examination would have been waived under section 38 of the German Tax Advisory Act. It was taken anyway.
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2006
Founded his own firm
Left the tax administration for private practice. Since 2009 the business has operated as a Steuerberatungsgesellschaft — a certified tax advisory company.
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2009
Certified as a Steuerberater
Chamber of Tax Advisers of Brandenburg. In the same year the advisory business became a certified tax advisory company.
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2015 – 2016
First contact with crypto assets
As an investor rather than an adviser. That period is the source of the practical familiarity with exchanges, wallets and the state of the data — the kind that cannot be acquired from literature.
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2017 – 2018
From investor to lecturer
The Berlin-Brandenburg tax advisers association asked whether anyone could teach on crypto currencies. That enquiry became the teaching work now carried out with chambers and associations throughout Germany.
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since 2021
Crypto assets full time
The practice reoriented entirely towards the taxation of crypto assets. Today: author, lecturer, expert witness before the Finance Committee of the German Bundestag, court-appointed expert, and claimant in five of his own proceedings.
Everything on proceedings, the hearing, teaching and publications
Why the order matters
Three stages that come together in everyday crypto work.
1989 – 1992
The programmer
Someone who has written assembler and COBOL is not intimidated by a file with two hundred thousand rows. That is the starting point of every crypto engagement: raw data no one can check by hand.
1997 – 2003
The audit division's IT officer
We introduced the IDEA audit software inside the tax office ourselves. Knowing how an auditor analyses data changes how you prepare it — and shows which demands are justified and which are not.
nine years
The tax auditor
Nine years on the other side of the table. That experience decides which position is worth defending and where a concession costs less than a dispute that will be lost anyway.
Offices, memberships and awards
- Steuerberaterverband BBVice-President and chair of the tax law committee
- Bitcoin BundesverbandFinance Director
- Blockchain BundesverbandCo-head of the tax working group
- IdStMember of the blockchain committee at the Institute for Digitalisation in Tax Law
- Potsdam Tax ForumAdvisory board
- Frankfurt (Oder) Regional CourtCourt-appointed expert, also for the local courts
- AwardNamed among the „Best Tax Advisers 2024“
Publications
Professional literature on the taxation of crypto assets — with Erich Schmidt Verlag, DATEV and self-published. All titles are in German.
New
01.09.2026
Krypto-Steuern und Auswandern
Crypto tax and emigration: exit taxation, the holding period and DAC 8, with eighteen destination countries compared. A practitioner's guide with a foundations section, eighteen country chapters and a practical part containing a departure timetable, model letters and a glossary. Self-published through Amazon Kindle Direct Publishing.
ESV
2nd edition 2027
Bitcoin und andere Kryptowährungen (currency token)
The fundamentals of taxation for crypto held as private and as business assets. Published by Erich Schmidt Verlag, ISBN 978-3-503-19153-6. The second edition appears in 2027, co-written with Gregor Danielmeyer in a non-official capacity.
Publisher
DATEV
2nd edition
Kryptowährungen in Steuer und Bilanz
Crypto in tax and financial accounting: practice material for firms that have to recognise crypto assets in business property. Second edition, available as an e-book.
Publisher
DATEV
E-book and print
Besteuerung von Kryptowährungen im Privatvermögen
Taxation of crypto held privately: material for advising private investors, from the holding period through rewards to entries in the return.
Publisher
In addition there are regular articles, among others at BTC-ECHO, as well as talks and seminars for chambers and associations. The full media list (in German)
For the press and event organisers
Enquiries about interviews, background briefings, expert opinions or specialist talks are answered promptly. On pending proceedings the rule is: we discuss the legal questions, not the clients.
German and English
Interviews, panels and written contributions in either language. Broadcast-quality remote setup available.
Photographs and biography
Portrait photographs by Jennifer Ängst and a short biography are available on request through the contact page.
As at: 25 August 2026. All statements are evidenced through the primary sources linked on the expertise page.
This English page mirrors the German biography, which additionally contains the full media list with articles, podcasts and recorded talks.
This English page mirrors the German biography, which additionally contains the full media list with articles, podcasts and recorded talks.