BAHR’s intellectual property practice advises on the full spectrum of contentious and non-contentious IP matters, with particular strength in patent litigation for multinational clients in the pharmaceutical, oil and gas, and aquaculture sectors. The firm also assists with licensing and enforcement strategies, as well as trademark, design, and marketing matters for consumer brands. The practice is led by patent litigator Eirik Basmo Ellingsen, with fellow patent litigation specialist Gunnar Sørlie serving as a key contact. Knut Sverre Skurdal Andresen joined from Advokatfirmaet Schjødt AS in 2026.

Legal 500 Editorial commentary

Accolades

Client satisfaction: Lawyer & team quality

Client satisfaction: Sector knowledge

Testimonials

Collated independently by Legal 500 research team.

'Anja Stensrud Elverum is the next generation star within legal IP advice.'
‘The firm combines solid technical knowledge with a pragmatic style of advice that is easy to apply in practice. They are dependable and manage matters with efficiency, which makes them straightforward to work with. Compared to others, the quality of service feels consistent regardless of who is involved.'
‘Partner Eirik Basmo Ellingson is an exceptional lawyer — incredibly bright, with a deep understanding of both the law and the technical issues at the heart of complex patent disputes. He remained calm and in complete control throughout the litigation, guiding his team and the client with absolute confidence and clarity. What truly sets him apart is his ability to translate intricate technical matters into clear, persuasive legal arguments, combined with his strategic insight and steady leadership. I value his composure, intellect, and the assurance he brings to every stage of a case.'
‘What makes this practice unique is the combination of deep legal expertise and exceptional technical insight. The team stands out for their ability to understand and articulate complex scientific and engineering concepts with remarkable clarity - an essential skill in patent litigation. They have not only mastered the nuances of both Norwegian and EPO law but also integrated this knowledge into creative, pragmatic strategies that make a tangible difference in the outcome of cases.'
‘The BAHR practice is one of the sharpest IP departments on the Norwegian market. They have great capabilities both within the contentious and non-contentious fields. The lawyers regularly represent clients in complex international IP matters.’
‘Anja Stensrud Elverum stands out through her combination of deep legal knowledge, commercial acumen, and exceptional client focus. She is consistently hands-on, precise, and proactive — with an ability to identify the core of complex issues quickly and to provide clear, strategic advice that is both legally sound and commercially practical. What truly differentiates her is her responsiveness and calm authority, which inspires confidence even in high-stakes matters. Anja’s combination of professionalism, accessibility, and strategic thinking makes her one of the most impressive IP lawyers we have worked with.’

Key clients

Amer Sports
Baker Hughes
Bayer
Biogen
Bristol-Myers Squibb
Equinor
Ewos AS
Neurim Pharmaceuticals
Novartis
Oslo Philharmonic Orchestra
REITAN
REMA 1000

Work highlights

Represented Bayer in complex patent litigation in Norway over its blockbuster drug Xarelto® (rivaroxaban), including invalidity and infringement actions brought by Sandoz and Glenmark.

Represented Biogen in ongoing patent litigation in Norway concerning Tecfidera®, a key treatment for multiple sclerosis with global sales of USD 100 billion annually.

Represented Tendeka AS and Swellfix UK Ltd on a patent dispute over autonomous inflow control systems for oil and gas fields.

Lawyers

Hall of Fame

The lawyers at the very top of the profession, widely known and respected by peers and clients for their longstanding involvement in market-leading work.