Klaus Ilmonen

Partner, Doctor of Laws
+358 9 2288 4378
+358 40 831 1868
Hanna-Mari Mudi

Assistant's telephone:

+358 9 2288 4382


Klaus Ilmonen heads our Capital Markets practice in Helsinki. His practice includes equity capital markets and other corporate transactions involving public corporations. He has considerable experience from public takeovers, as well as from cross-border transactions. He also works with governance of public corporations.
Klaus has served on a consultative group for developing EU corporate finance regulation and has participated in drafting Finnish takeover regulation. He also teaches securities regulation at the University of Helsinki.
Klaus has qualified as an attorney in the State of New York, and practised U.S. securities law in the London office of the law firm Cleary, Gottlieb, Steen & Hamilton, where he represented European issuers and underwriters in international securities offerings. He also worked on international M&A transactions.
Klaus has been a visiting researcher at Harvard Law School, he holds a LL.M. degree from Columbia Law School in New York and a doctorate in law from the University of Helsinki.

He has served as an officer with Finnish forces in Kosovo and Afghanistan. He has lectured on operational law in Finland and abroad.


  • Counsel to EVRY in the combination of Tieto and EVRY through a cross-border merger , 2019 
  • Counsel to Outotec in the combination of Outotec and Metso Minerals through a demerger, 2019.
  • Counsel to Glaston Corporation in connection with its EUR 34 million rights issue and listing of new shares on Nasdaq Helsinki, 2019
  • Counsel to Investors on the SEK 1.2 Billion Directed Share Issue in ÅF, 2019.
  • Counsel to Pöyry Plc in ÅF’s recommended public cash tender offer for all shares in Pöyry, 2018.
  • Counsel to Kildare Partners in its public tender offer for Technopolis Plc, a Finland-based listed company providing offices, coworking spaces and related services, 2018. The transaction is valued at approximately EUR 730 million.
  • Counsel to Asiakastieto Group Plc in its acquisition of UC AB in Sweden (valued EUR 340 million), 2018.
  • Counsel to Terveystalo in its IPO and listing on the Nasdaq Helsinki stock exchange, 2017.
  • Counsel to lead manager SEB (publ.) Helsinki branch in the transfer of Robit Oyj from First North Finland to the main list of Nasdaq Helsinki, 2017.
  • Counsel to Powerflute Oyj in the recommended cash offer for Powerflute by Nordic Packaging and Container (Finland) Holdings Oy an affiliate of Madison Dearborn Partners, LLC. 2016.
  • Counsel to Alma Media Corporation on its exchange offer for the shares and options in Talentum Oyj.
  • IPO of Asiakastieto Group Oyj - Counsel to the issuer, 2015.
  • IPO of Verkkokauppa.com Oyj - Counsel to the issuer, 2014.
  • OP-Pohjola Group EUR 3,3 billion tender for Pohjola Bank - Counsel to Pohjola Bank, 2014.
  • Counsel to Microsoft Corporation on its Acquisition of Nokia Devices & Services from Nokia Corporation for EUR 5,44 billion, 2013.


  • "Impeccable legal knowledge and commercial understanding.", IFRL1000, 2020
  • 'He is described as "very experienced and knowledgeable" by clients. Another client states that Ilmonen "shows great ability to be pragmatic when needed."', Chambers Europe 2019
  • Ranked as a Market leader in Capital Markets in the 2019 & 2020 editions of IFLR1000
  • "Sources say that Klaus Ilmonen is 'responsive, pragmatic and easy to work with. He is also extremely experienced and knowledgeable so he really ticks all the boxes.' One interviewee enthuses: 'Klaus is a clear professional in all aspects: technical knowledge, commercial awareness, effectiveness and client service.'", Chambers Europe 2018
  • "Sources describe him as an 'experienced partner, very diligent and knowledgeable' with 'superb skills in all relevant areas.' Clients also note that 'he is a positive person who always wants to make sure whatever needs to be done gets done.', Chambers Global 2018
  • Ranked among the best lawyers in Capital Markets in the 2015-2018 editions of Chambers Europe
  • "Klaus Ilmonen is ‘one of the few experienced lawyers in the Finnish IPO market’ ", Capital Markets, Legal 500, 2015
  • Ranked as a Leading individual in Capital Markets in the 2018 and 2019 edition of Legal 500
  • Ranked as a Highly regarded  lawyer in Capital Markets in the 2014, 2015, 2016, 2017 and 2018 editions of IFLR1000
  • Ranked among the best lawyers in the 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016 and 2017 editions (Helsinki: Capital Markets, Mergers and Acquisitions) of Best Lawyers®


  • Member of the Consultative Working Group on Corporate Finance of the European Securities Markets Authority (ESMA)
  • Member of the expert group on securities regulation of the Finnish Bar Association
  • Managing director of the Mannerheim Foundation


  • Doctor of Laws, University of Helsinki, 2016
  • Harvard Law School, Visiting Researcher, 2011 - 2012 (Jan.)
  • Partner, Hannes Snellman, 2007
  • Associate, Cleary, Gottlieb, Steen & Hamilton, London, 1999 - 2002
  • LL.M. (Stone Scholar), Columbia University, 1999