Three new partners at MDDP

As of 1 April 2026, the partnership at tax consultancy firm MDDP has expanded to include three new members. The new partners are: Jakub Warnieło in the Tax and Litigation Team, Rafał Sidorowicz in the Personal Tax and Employer Advisory Team, and Gniewomir Parzyjagła in the Income Tax and Real Estate Teams.

– The addition of three new Partners to the team marks an important milestone in MDDP’s development, confirming our strategic focus on expanding our tax advisory services and responding to our clients’ growing needs in this area. The group of Partners is being joined by experienced experts and leaders who have been building strong relationships with clients for years, developing their teams and having a tangible impact on our organisational culture and MDDP’s position among the leaders of the tax industry – says Tomasz Michalik, CEO of MDDP.

In addition to their day-to-day work, the new Partners will focus, among other things, on tax compliance relating not only to tax audits but also to the growing number of inspections, as well as the effectiveness of various employment and remuneration structures. They will develop MDDP’s operations in the regions, strengthen support in the issues relating to the taxation of cryptocurrencies and the reporting of profits from digital activities , and criminal tax matters, including those relating to the joint and several liability of board members and sanction proceedings, such as those concerning trade with Russia and Belarus.

New MDDP Partners

Gniewomir Parzyjagła has been assisting clients in the areas of CIT and international taxation for almost two decades. He specialises in advising on the taxation of business activities, including cross-border operations, withholding tax and MDR. He leads restructuring projects, including those concerning effective investment structures. He combines expert knowledge with a practical approach to business. He helps clients manage their tax affairs safely and in compliance with regulations (including those concerning tax avoidance), and represents them in tax proceedings.

Rafał Sidorowicz specialises in PIT and social security (ZUS) tax, advising Polish and international employers – particularly in demanding sectors such as IT, new technologies, engineering  in the energy sector and real estate. He has extensive experience in designing advanced remuneration models and providing comprehensive support for cross-border employees. He successfully supports clients, including those in the HNWI segment, expats and investors in income taxation – including cryptocurrency, capital and property – ensuring the security and compliance of settlements in an international environment. He is a trainer and lecturer; he teaches at, amongst others, the Warsaw School of Economics and Kozminski University.

Jakub Warnieło is Head of the Tax and Litigation Team at MDDP. He represents clients at all stages of proceedings before tax authorities and administrative courts. He acts as counsel in cases before the Court of Justice of the European Union. He leads projects related to tax safety, implements procedures to protect against liability, supports clients during audits (including preparations for audits) and tax risk reviews. His experience  and effectiveness have been recognised on numerous occasions internationally – he is the winner of the Tax Litigation Lawyer of the Year award at the ITR EMEA Tax Awards 2025 and the leader of the team honoured with the title of Tax Disputes Advisory Firm of the Year 2025 in the EMEA region. He also regularly features  in prestigious national and international rankings, such as International Tax Review, World Tax, Rzeczpospolita’s Tax Advisory Firms Ranking and Dziennik Gazeta Prawna’s Tax Firms and Advisers Ranking. He is the author of publications on tax law and a lecturer at the Warsaw School of Economics.