• 2015-

    Representing Total E&P

    Hanne represents Total E&P in a tax case regarding transfer pricing for corporate overhead charges. She took over this role in 2015, as the case was headed towards the Borgarting appeal court. In December 2015, the appeal court gave a ruling which overturned the tax assessment in respect to key issues.

  • 2012

    The Transocean criminal case

    Hanne represents Transocean in a series of tax cases, and also acts as co-defence counsel for the indicted companies in the ”Transocean criminal case”, where the prosecution originally alleged that tax had been evaded on some NOK 11 billion in income. The indictment included several diverse topics, such as the legality of a group contribution, exit taxation, dividend distribution and tax filing obligations. In the county court, all indicted were fully acquitted on the grounds that no tax had been evaded. The appeal was scheduled for January - June 2016 but the case was ceased after the prosecution made a request for full acquittal.

Work experience

  • 2015–
    Partner, Oslo office, Thommessen
  • 2014–2015
    Managing Partner, Arntzen de Besche
  • 2012–2015
    Partner, Arntzen de Besche
  • 2005–2012
    Partner, Law firm PricewaterhouseCoopers AS
  • 2005–1998
    Associate/lawyer/senior lawyer, Law firm PricewaterhouseCoopers AS
  • 2005
    Admitted to the Supreme Court of Norway
  • 1986–1998
    Auditor assistant/senior/manager, Price Waterhouse A.S.


  • 1994–1998
    Candidate in Jurisprudence, University of Oslo
  • 1983–1986
    Licence en Sciences Économiques, Université de Lausanne
  • 1981–1983
    International Baccalaureate, St Clare’s Hall, Oxford


  • Revisjon & Regnskap 5/2015: I want to see my file! Regarding access to documents in tax cases


  • Revisjon & Regnskap 4/2015: Transocean and group contributions: legal basis for distributions during liquidation


  • Revisjon & Regnskap 2/2015: Termination of tax residency in Norway: where does a company reside?


  • Revisjon & Regnskap 5/2013: The Company Act § 3-8: Still not so simple