Advokatfirmaet Thommessen AS advises a broad client base that includes major multinationals, private equity funds, and seed-capital investors on the full spectrum of tax matters. The team is particularly strong in direct, indirect, and property tax, and is frequently engaged in complex litigation as well as tax issues arising in the equity and debt markets, joint ventures, and fund formation. Practice head Marius Holm Rynning is noted for his deep expertise in international tax law, and he is supported by tax dispute specialist Finn Backer-Grøndahl and experienced litigator Ståle Kristiansen. The team was further strengthened by the promotion of restructuring specialist Camilla Bergby to partner in January 2025.

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Accolades

Client satisfaction: Sector knowledge

Client satisfaction: NPS ®

Testimonials

Collated independently by Legal 500 research team.

‘Great professional expertise.'
‘Thommesen is a professional legal adviser on tax and VAT. They deliver efficiently, on time, and with high quality. Responses to inquiries are very quick, and clients are involved in an effective manner.’
‘Solid law firm that supports across tax and similar practice areas like corporate finance and employment rights.’
‘Ståle Kristiansen is a very hands-on adviser who is knowledgeable and good at building trust.’
‘Thommessen’s tax team consists of skilled, competent lawyers with strong commercial understanding and insight. They are pleasant to work with, which helps lead to quicker solutions.’
‘Above all, it is the ability to understand the commercial challenges and translate them into sound legal advice. Finn Backer-Grøndahl stands out in this regard. ’

Key clients

Fresenius Kabi
Equinor
Statkraft
Alcoa Corporation Inc
Storebrand
DNB
Odfjell SE
Sølvtrans AS
Intership AS
Aqua Group AS
Westfal Larsen AS
Masterbulk Pte Ltd

Work highlights

Advised on the restructuring of Aeternum Capital and the redemption of WQZ.

Represented a client on litigation related to a major loss tax deduction.

Represented ISS Facility Services in a NOK 100 million VAT litigation related to a matter of principle for all operators of business canteens in Norway, with a successful outcome for the client.

Lawyers

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