Anna-Maria Tamminen

Partner | Helsinki
English, Finnish, Swedish, French, German

Anna-Maria specialises in commercial arbitration and litigation, with a special focus on complex and international disputes. She currently represents parties in national and international arbitrations, as well as administrative and civil litigations both in Finland and Sweden.

Anna-Maria has experience in mediating, litigating and arbitrating high-stakes commercial disputes often consisting of parallel proceedings in the fields of general commercial law, international sales, post M&A, competition law, international investment, energy and telecoms. She has arbitrated cases under the FAI Rules, SCC Rules, ICC 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.

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.

Sources highlight her strong international capabilities, adding that they 'sing her praises highly' and that she is 'seriously impressive.

Chambers Global 2019 | Dispute Resolution


Represents a European State in the setting aside proceedings of an investment treaty award before the Svea Court of Appeal and Swedish Supreme Court, Stockholm.

Represented UPM-Kymmene Oyj in the largest ever Finnish follow-on damages litigation in which Metsähallitus originally claimed a capital amount of nearly 282 million euros in damages jointly and severally from Finnish forestry companies Stora Enso, UPM and Metsäliitto.

Represented an international manufacturer against a Nordic company in a multibillion SEK dispute arbitrated in Stockholm under the SCC Rules and Swedish applicable law.

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 a Danish corporation in a high-value engineering dispute mediated and arbitrated in Copenhagen under the DIA Rules and Danish applicable law.

  • 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 Co-arbitrator, Sole Arbitrator and Chairperson on arbitral tribunals constituted under the ICC, SCC, DIA, LCIA and FAI Rules governed by Finnish, Swedish, Danish, English, Cypriot and Swiss applicable law.


  • Recommended in Dispute Resolution, Legal 500, 2021
  • 'Anna-Maria Tamminen assists with post-M&A and competition-related disputes. She is reputed for her expertise in arbitration, frequently acting on international cases.', Dispute Resolution, Chambers Global and Chambers Europe, 2021
  • Ranked as Future Leader, Who’s Who Legal Arbitration (Finland), 2021
  • 'Anna-Maria Tamminen is a very good lawyer with great international exposure which we appreciate. Coupled with a fundamental understanding of the legal issue, Anna-Maria Tamminen distils from the complex and provides a concise, hands-on and actionable path forward. Anna-Maria Tamminen is sharp, quick off the mark and capable of providing strategic advice.', Dispute Resolution, Legal 500, 2020
  • 'Sources state that she is "very hard-working."', Dispute Resolution, Chambers Global and Chambers Europe 2020
  • Ranked as one of the Thought Leaders and Global Leaders in the Who's Who Legal – Arbitration (Finland) 2020 edition
  • Ranked as “rising star” for Commercial Arbitration/Finland in the 2019 edition of Euromoney's LMG Rising Stars, Expert Guides, Legal Media Group
  • "Sources highlight her strong international capabilities, adding that they 'sing her praises highly' and that she is 'seriously impressive.'" Dispute Resolution, Chambers Global 2019
  • Ranked as one of the Thought Leaders in the Who's Who Legal – Arbitration (Finland) 2019 edition
  • “Excellent knowledge and experience on the EU law field as well as investment arbitration.” Benchmark Litigation 2018
  • ’Anna-Maria Tamminen stands out for being “very well versed in international disputes and arbitration.” Clients also appreciate her “quick response times” and ability to “listen to the client.” ', Dispute Resolution, Chambers Europe 2018
  • Ranked as one of the World’s leading Arbitration lawyers (Finland), Who’s Who Legal: Arbitration 2018
  • Selected by clients and peers as Who’s Who Legal’s Thought Leader in Arbitration for 2020, along with only two other Finnish lawyers.
  • Ranked as a notable practitioner (Dispute Resolution), Chambers Europe 2018
  • Ranked as "a Rising Star" in Commercial Arbitration, Expert Guides, Legal Media Group 2018
  • One of the most highly ranked individuals in the non-partner category of Who’s Who Legal 2017: Future Leaders – Arbitration and described as “persistent and experienced for her age, dedicated and bright”
  • Ranked as “a rising star” in the 2015 edition (Dispute Resolution) of Chambers Europe 2015, described as “really capable and good in international cases” in the 2016 edition (Dispute Resolution) of Chambers Europe 2016, recognised as an “associate to watch” in the 2017 edition (Dispute Resolution) of Chambers Europe 2017
  • Ranked among the best lawyers in the 2014, 2015, 2016, 2017 and 2018 editions (Helsinki: Arbitration and Mediation, Litigation) of Best Lawyers®

Memberships and Positions of Trust

  • Finnish Bar Association, member
  • Attorney-at-law and Counsellor in the State of New York, USA


  • Swedish Arbitration Association, Executive Committee, 2019-
  • ICC Court of Arbitration, alternate member representing Finland, 2018-
  • Member of the Civil Procedure Law Expert Committee of the Finnish Bar Association, 2018-
  • International Chamber of Commerce, Commission on Arbitration and ADR, member representing Finland (2014-), Task Force “Maximising the Probative Value of Witness Evidence” member (2016-)
  • ASA below 40, international co-Chair (2017-)
  • London Court of International Arbitration, Young International Arbitration Group, Co-Chair (2013-2017)
  • Young Arbitration Club Finland, past Chair (2012-2014) and Founding Member
  • Member of the Finnish Arbitration Association, European Users’ Council of London Court of International Arbitration (LCIA), Association Suisse de l’Arbitrage (ASA), Swedish Arbitration Association (SAA), ICC Young Arbitrators Forum (ICC YAF), Young Austrian Arbitration Practitioners (YAAP), Young Arbitrators Sweden (YAS)


  • Journal of International Arbitration, member of the Editorial Board (2015-)
  • ITA Board of Reporters, country reporter for Finland (2015-)


  • Co-author of the article "SCC Express: A Shortcut or A Detour?" in the Kluwer Arbitration Blog (2021) 
  • Co-author of the Finnish Chapter in the Global Practice Guide: Litigation 2020 by Chambers & Partners (2020)
  • Getting the Deal Through – Arbitration Finland Chapter together with Lehto, Tyynysniemi, and Rautiainen (2020)
  • Getting the Deal Through – Arbitration Finland Chapter together with Järvinen, Lehto and Tyynysniemi (2019)
  • Chambers eDiscovery & Disclosure Guide Finland Chapter together with Bygglin, Heikkinen K. and Heikkinen T. (2019)
  • Getting the Deal Through – Arbitration Finland Chapter together with Järvinen, Bygglin and Heikkinen (2018)
  • Chambers eDiscovery & Disclosure Guide Finland Chapter together with Järvinen, Bygglin and Heikkinen (2018)
  • Arbitration Agreement in Ehrström, Timonen, Turunen (Ed.) Arbitration in Finland, YACF publication (2017)
  • Issue Conflicts as Basis for Challenge of an Arbitrator – A new First in Nordic Arbitration Practice? Scandinavian Series of Law vol. 63 (2017), p. 331-354
  • Case comment “Finland: A Party Can Recover Costs of Court Proceedings for Interim Measures in a Subsequent Arbitration” in ICC Dispute Resolution Bulletin 2017 Issue 2
  • Kluwerarbitration blog “Arbitrator-ordered Costs of Injunctive Relief Proceedings in National Court: When Should a Party Be Able to Recover its Costs?” 6 April 2017
  • Several case comments for ITA Board of Reporters (together with Mika Savola), Kluwer Arbitration (2015-2016)
  • “The Obligation to Pay the Advance on Costs under the Vienna Rules and Austrian Law”, Austrian Arbitration Yearbook 2009, Manz (2009)

Education and Professional Background

  • Skiljemannautbildningen (SAA and SCC arbitrator training) 2016-2017
  • FAI (Arbitration Institute of the Finland Chamber of Commerce) Arbitration Academy, 2014
  • 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


  • Partner, Hannes Snellman Attorneys Ltd, Helsinki 2018-
  • Managing Associate, Hannes Snellman Attorneys Ltd, Helsinki 2016-2017
  • Senior Associate, Hannes Snellman Attorneys Ltd, Helsinki, 2011-2015
  • Foreign Associate, Wilmer Cutler Pickering Hale and Dorr LLP, London, 2006-2010
  • Internships at law firms and ministries in the United Kingdom, Finland and Austria

Recent Speaking Engagements

  • May 2019, IFCAL Conference, Helsinki, moderator
  • April 2019, Copenhagen Arbitration Day, Copenhagen, speaker
  • March 2019, Future of International Arbitration, London, speaker
  • February 2019, Winter Academy, University of Vienna, Austria, speaker
  • December 2018, CEA Mediation Commission event, Madrid, speaker
  • November 2018, ASA below 40, Fall Seminar, Zurich Switzerland, Co-chair
  • October 2018, Swedish Law Day, Moscow, speaker
  • October 2018, GAR Live Vienna, Vienna Austria, Panellist
  • September 2018, Swedish Arbitration Days, Stockholm Sweden, Panellist
  • May 2018, LCIA European Users’ Council Symposium, Tylney Hall, co-chair
  • April 2018, Summit on Global Dispute Resolution, New York, panellist
  • April 2018, DIS40 Spring Seminar, Zurich, panellist
  • April 2018, ICAL Programme University of Stockholm, Stockholm, lecturer
  • March 2018, SCC Seminar on Investment Arbitration, Warsaw, panellist
  • March 2018, Cross-border transactions course, University of Helsinki, lecturer

Read More About Anna-Maria

Blog Posts by Anna-Maria Tamminen