Anna-Maria Tamminen

Managing Associate
+358 9 2288 4484
+358 40 550 0687
Sonia Tani

Assistant's telephone:

+358 9 2288 4522

Assistant's e-mail:


Anna-Maria specialises in commercial arbitration and litigation, with a special focus on complex international disputes. She currently represents parties in commercial and investment arbitrations as well as private enforcement cases.

Before joining Hannes Snellman, Anna-Maria worked for several years as a foreign associate in the International Arbitration Group of WilmerHale in London. Anna-Maria is trained in both common and civil law legal systems and is admitted to practice as an attorney both in Finland and the State of New York. Due to her training and work experience in Finland, Austria, United Kingdom, United States and Sweden, Anna-Maria has an in-depth understanding of both common and civil law legal systems.

Anna-Maria has experience in mediating and arbitrating high-stakes commercial disputes often consisting of multijurisdictional, parallel proceedings in the fields of general commercial law, international sales, post M&A, competition law, telecoms, energy and oil & gas under the ICC Rules, SCC Rules, FAI Rules, Vienna Rules, LCIA Rules, DIA Rules, UNCITRAL and PCA Rules. Anna-Maria has additionally advised clients with regard to potential commercial and investment disputes and on the recognition, enforcement and setting aside of arbitral awards in a variety of jurisdictions.

Anna-Maria also acts as arbitrator in both international and domestic disputes. She regularly publishes articles, presents at conferences and lectures on dispute resolution topics.


  • Ranked as "an associate to watch" in the 2017 edition (Dispute Resolution) of Chambers Europe

  • One of the most highly ranked individuals in the non-partner category of Who’s Who Legal: Future Leaders – Arbitration and described as “persistent and experienced for her age, dedicated and bright”

  • Described by clients as "really capable and good in international cases" (Dispute Resolution) Chambers Europe 2016

  • Ranked as "a rising star" in the 2015 edition (Dispute Resolution) of Chambers Europe 2015

  • Ranked among the best lawyers in the 2014, 2015 and 2016 editions (Helsinki: Arbitration and Mediation, Litigation) of Best Lawyers®


  • Continues to represent a Finnish listed company in precedent-setting private enforcement cases where the total value in dispute is approximately EUR 200 million

  • Represented a Central European company against a Russian corporation in a multimillion dollar dispute arbitrated in Stockholm under the SCC Rules and Russian and Swedish applicable law

  • Represented a Finnish listed company against one of the largest Danish corporations in a high-value engineering dispute mediated and arbitrated in Copenhagen under the DIA Rules and Danish applicable law

  • Represented a Finnish company against a Russian company in relation to a multimillion euro joint venture shareholders’ dispute arbitrated in Finland under the FAI Rules and Finnish applicable law

  • Represented a major Finnish company in an ad hoc arbitration where Claimant sought the adjustment of allegedly unreasonable contractual provisions under Section 36 of the Contracts Act in connection with the termination of a long-term energy co-operation agreement

  • Represented a European telecommunications company in a long-running ICC arbitration with a French corporation arising out of a joint venture located in Eastern Europe, with several billion euros in dispute

  • Represented a European telecommunications company in long-running, parallel VIAC arbitrations relating to a shareholder agreement

  • Represented the SPLM/A (South Sudan) in its boundary dispute with the Government of Sudan in the so-called Abyei arbitration under the auspices of the PCA

  • Continuously advises Finnish and foreign parties in the drafting of contracts, especially with regard to dispute resolution provisions, as well as in the preparation of claims and settlement of disputes

  • Acted as sole arbitrator in an SCC dispute between a Swedish and a Cypriot party governed by Cyprus and Swedish law

  • Acted as sole arbitrator in an SCC dispute between a Swedish and an Estonian party governed by Swedish law

  • Acted as sole arbitrator in an SCC dispute between a Swiss and a Swedish party governed by Swedish law

  • Acted as co-arbitrator in an SCC dispute between a Danish and an Estonian party governed by Danish and Swedish law

  • Counsel to Veolia in a JV with Neste and Borealis to build a new combined heat and power plant and produce and supply steam and other utilities to Neste's refinery and Borealis' petrochemical plant in Porvoo, Finland

  • Counsel to Biotie Therapies Corp. in the public tender offer of the shares and other securities in Biotie Therapies by Acorda Therapeutics


  • Skiljemannautbildningen (SAA and SCC training for arbitrators), 2016-2017

  • FAI Arbitration Academy, 2014

  • LL.M. in International Business Regulation, Litigation and Arbitration, New York University School of Law, USA 2011 (Fulbright Scholar)

  • Master of Laws, University of Turku, Finland 2006

  • Erasmus exchange year, University of Vienna, Austria 2004-2005


  • Managing Associate, Hannes Snellman Attorneys Ltd, Helsinki 2016-

  • Senior Associate, Hannes Snellman Attorneys Ltd, Helsinki, 2011-2015

  • Foreign Associate, Wilmer Cutler Pickering Hale and Dorr LLP, London, 2006-2010


  • Finnish Bar Association, member

  • New York State Bar, member


  • London Court of International Arbitration, Young International Arbitration Group, Co-Chair (2013-)

  • International Chamber of Commerce, Commission on Arbitration and ADR, member representing Finland (2014-)

  • Young Arbitration Club Finland, past Chair (2012-2014) and Founding Member

  • Member of the Finnish Arbitration Association, LCIA European Users’ Council, ICC Young Arbitrators Forum, Young Austrian Arbitration Practitioners, Young Arbitrators Sweden

  • ITA Board of Reporters, country reporter for Finland (2015-)

  • Journal of International Arbitration, member of the Editorial Board (2015-)


  • Case comment for ITA Board of Reporters, Metsäliitto Osuuskunta, Metsä Board Oyj v. UPM-Kymmene Oyj, District Court of Helsinki, Case No. L 14/19338, Decision No. 15/26976, Case Date 18 June 2015 (together with Mika Savola), Kluwer Arbitration 2016

  • Several case comments for ITA Board of Reporters (together with Mika Savola), Kluwer Arbitration (2015)

  • The Obligation to Pay the Advance on Costs under the Vienna Rules and Austrian Law, Austrian Arbitration Yearbook 2009, Manz (2009)


  • September 2016, Costs, interest and other necessary stuff that causes problems in international arbitration, IBA Annual Conference Washington DC, speaker

  • September 2016, YIAG Symposium, Tylney Hall, co-Chair

  • June 2016, UNCITRAL Model Law – Different Cultures, Different Approaches, DIS40 and ICC YAF seminar, Riga, panelist

  • May 2016, YIAG Symposium, Tylney Hall, co-Chair

  • May 2016, YIAG Symposium, Moscow, co-Chair

  • April 2016, Young Arbitrators Sweden, YAS Arbitration Update, Stockholm, panelist

  • March 2016, University of Helsinki, cross-border transactions course, lecturer

  • March 2016, Young Practitioners Symposium co-presented by IBA Arb40 and YIAG, moderator

  • February 2016, Stockholm University, ICAL program, lecturer

  • January 2016, Nordic General Counsel Summit, Stockholm, moderator

  • September 2015, YIAG Symposium, Tylney Hall, co-Chair

  • July 2015, Austrian Arbitration Academy, lecturer

  • May 2015, YIAG Symposium, Tylney Hall, co-Chair

  • May 2015, YIAG Symposium, Moscow, co-Chair

  • April 2015, ICDR Y&I debate, Geneva, speaker

  • March 2015, YIAG and Moot Alumni Association event “YIAG meets Vis”, speaker

  • March 2015, ASA below 40 / ICC YAF seminar, Geneva, speaker