Heidi Yildiz is a dual-qualified Barrister and Finnish attorney with a broad international arbitration and commercial litigation practice.

Before coming to the Bar, Heidi practised as a solicitor for more than 12 years. She has practised international arbitration and commercial litigation extensively both in London and Helsinki. Heidi is a fellow of the Chartered Institute of Arbitrators and is also developing a practice as an arbitrator. Heidi is recognised in the Legal500 Arbitration Powerlist UK 2022 and 2023 as a leading International Arbitration Counsel in the UK and has since 2018 been recognised by Who’s Who Legal Arbitration as one as one of the World’s future arbitration leaders.

Heidi has more than 14 years of experience as a counsel in complex and high-value international arbitration disputes, both of a private and public law nature. Heidi has represented a broad range of clients across a range of different industry sectors in institutional arbitrations conducted under the ICC, LCIA, DIS, FAI, LMAA, UNCITRAL and PCA Rules as well as ad hoc arbitrations, governed by a variety of substantive and procedural laws.

In addition to commercial litigation experience at English courts, she has gained a broad commercial litigation experience at all stages of a dispute and at all levels of court in Finland.

Heidi trained first as a solicitor in the London office of Wilmer Hale and upon qualification in January 2009 practiced international arbitration there until 2011. Her experience at WilmerHale included working as part of a team that successfully represented SPLM/A in the ground-breaking Abyei boundary delimitation proceedings against the Government of Sudan conducted under the auspices of the Permanent Court of Arbitration in The Hague. Thereafter, she worked nearly ten years at a leading Finnish firm, Dittmar & Indrenius in Helsinki until she transferred to the English Bar in July 2021 and joined 36 Stone.

Heidi is Direct Access accredited barrister. Accordingly, members of the public are able to instruct her without the need to instruct an intermediary such as a solicitor.

Key cases & testimonials

Representing an international seafood company and charterers in four separate multi-million LMAA arbitration proceedings concerning the performance of long-term charterparties for the carriage of fish, seated in London and governed by English law.

Successfully represented a property developer in the High Court (Business and Property Courts) in Manchester on an interim application relating to GBP 4 million fraud allegation and related injunction proceedings.

As a sole counsel representing and advising a publicly listed Nordic forest products company in a potential gross-border ICC arbitration against a global media company, arising from a non-executed sales agreement, seated in London and governed by English law. Assisted the client with securing a favourable settlement.

Acted as a sole arbitrator in arbitration proceedings under the FAI Rules arising from a shareholders’ agreement in the media and entertainment sector, governed by Finnish law and seated in Helsinki.

Heidi is a very clever and extremely dedicated counsel [...] Her dual-qualified status and market experience makes Heidi a compelling choice.Who's Who Legal Arbitration Future Leaders 2023
Heidi is everyone's go-to for arbitration in Finland [...] She always sees the bigger picture.Who's Who Legal Arbitration Future Leaders 2022
An analytic and strategic thinker, renowned for her [...] in-depth knowledge of both civil and common law principles, [...] definitely recommend her in any arbitration.Who's Who Legal Arbitration Future Leaders 2020

Areas of expertise

Heidi accepts instructions in all areas of international arbitration, including Investment Treaty Arbitration, and has been involved in numerous high-value, complex and multi-jurisdictional disputes across a range of different industry sectors.

Recent work includes:

Representing an international seafood company and charterers in four separate multi-million LMAA arbitration proceedings (heard concurrently) concerning the performance of long-term charterparties for the carriage of fish, seated in London and governed by English law.

Advising on a London seated ad hoc arbitration arising from a partnership agreement and governed by English law.

As a sole counsel representing and advising a publicly listed Nordic forest products company in a potential gross-border ICC arbitration against a global media company, arising from a non-executed sales agreement and changed circumstances caused by the increased oil prices, seated in London and governed by English law. Assisted the client with securing a favourable settlement of the dispute;
As a lead counsel successfully acting for a long-standing Finnish manufacturer in potential FAI and LCIA arbitration proceedings against several European subsidiaries of a Chinese long-established manufacturing company, arising from the parties’ joint infrastructure projects in several European locations, governed by both Finnish and English law. Secured a highly favourable settlement of the dispute;
Acting as a Finnish co-counsel for a leading global IT services company in ICC arbitration proceedings against a major Nordic telecommunications company, seated in Helsinki and governed by Finnish law, arising from services agreements in the telecommunications field;

Advising a leading Nordic publicly listed telecommunications company in potential ICC arbitration proceedings, seated in Helsinki and governed by Finnish law, arising from a joint-venture agreement in the technology sector.

Advising a European construction company in potential ICC arbitration proceedings, seated in Helsinki and governed by Finnish law, arising from a FIDIC contract relating to a construction of a renewable energy oil refinery.

As a co-lead counsel, successfully advising and acting for a major Finnish Media Corporation in FAI arbitration proceedings against a Swedish publicly listed Media Company and its Finnish subsidiary in a dispute over domain name licence and associated trademark rights, arising from an asset purchase agreement, seated in Helsinki. Also successfully acted for the same client in related interim injunction proceedings at all procedural stages, including the Supreme Court of Finland, as well trademark proceedings in the Market Court in Finland and arbitral award enforcement proceedings in the District Court of Helsinki and Svea Court of Appeal in Stockholm.

As a co-lead counsel, successfully advising and acting for a leading global bio and forest products company in a multi-million-euro International Arbitration under the FAI Rules, arising from supply and purchase agreement relating to the construction of a state-of-art biorefinery, governed by Finnish law, seated in Helsinki. Successfully also advised the same client in potential FAI arbitration proceedings against a Finnish subsidiary of a leading multinational shipping and logistics company arising from a long-term logistics agreement, governed by Finnish law, seated in Helsinki.

As a co-lead counsel, successfully advising and acting for a Finnish subsidiary of a leading global technology company in an International Ad Hoc Arbitration dispute arising from a purchase contract relating to a large construction project in the Middle East, seated in Helsinki;

Successfully advising and acting for a major European manufacturer in a multimillion-euro international ad hoc arbitration concerning the supply of a production line to a Finnish Company, seated in Helsinki;

Successfully advising and acting for an English subsidiary of a leading international construction company in a multimillion-euro ICC Arbitration dispute against a leading constructor of power plants, arising from a supply and purchase agreement in the construction field, seated in Stockholm. Also represented the same client in Finnish court litigation proceedings concerning a claim for unjust enrichment brought by the parent company of the same opponent.

Successfully advising and acting for a cargo airline in an LCIA Arbitration dispute concerning an aircraft lease agreement, governed by English law, seated in London;

Successfully advising and acting for an international media company in a multi-million-euro International Arbitration dispute arising from a joint venture agreement in the telecommunications field, governed by the DIS Rules, seated in Munich;

As part of WilmerHale’s team, successfully representing SPLM/A in boundary arbitration proceedings against the Government of Sudan (the Abyei arbitration, PCA).

In addition to the counsel work, Heidi accepts appointments as arbitrator directly from parties and via arbitral institutions in all areas of international arbitration. Heidi is a fellow of the Chartered Institute of Arbitrators. Recent arbitrator appointments include:

Acted as a sole arbitrator in arbitration proceedings under the FAI Rules arising from a shareholders’ agreement in the media and entertainment sector, governed by Finnish law and seated in Helsinki;
Acting as a sole arbitrator in FAI arbitration proceedings between a Finnish innovation consultancy company and a Finnish carpentry company in a dispute over a consultancy agreement, governed by Finnish law and seated in Helsinki.

Heidi accepts instructions in all areas of commercial litigation and has been involved in numerous high value, complex and multi-jurisdictional disputes.

Recent work includes:

Successfully represented a property developer in the High Court (Business and Property Courts) in Manchester on an interim application relating to GBP 4 million fraud allegation and related injunction proceedings.

Acted as a lead counsel for a Dutch seller of luxury yachts in litigation proceedings in the District Court of Helsinki against a Finnish purchaser. Secured a favourable judgment for the client.

As a co-lead counsel advising and representing several global insurance companies and owners of oil and chemical tankers, flagged in Malta, against a leading global provider of marine and energy solutions and services in a multi-million-euro maritime dispute in the District Court of Pohjanmaa, concerning the supply of unfit propulsion systems to the tankers.

As a lead counsel successfully advising and acting for an acclaimed international airline in highly unusual proceedings in the District Court of Helsinki arising from a terrorist attack in an African state. Secured a favourable settlement of the dispute.

Arbitral award enforcement proceedings in the District Court of Helsinki, Finland and Svea Court of Appeal in Sweden, following successful arbitral proceedings under the FAI Rules, seated in Helsinki.
As a co-lead counsel, successfully advising and acting for a major Finnish Media Corporation against a Swedish publicly listed Media Company in trademark proceedings in the Market Court in Finland. Also successfully representing the same client in related interim injunction proceedings at all procedural stages, including the Supreme Court of Finland.

Heidi accepts instructions in disputes concerning construction, energy and infrastructure or related projects and has been involved in numerous high-value, complex and multi-jurisdictional disputes.

Recent work includes:

As a co-lead counsel, successfully advising and acting for a leading global bio and forest products company in a multi-million-euro International Arbitration under the FAI Rules, arising from supply and purchase agreement relating to the construction of a state-of-art biorefinery, governed by Finnish law, sited in Helsinki;

Advising a leading European construction company in potential ICC arbitration proceedings, seated in Helsinki and governed by Finnish law, arising from a FIDIC contract relating to a construction of a renewable energy oil refinery;

Successfully advising and acting for an English subsidiary of a leading international construction company in a multimillion-euro ICC Arbitration dispute against a leading constructor of power plants, arising from a supply and purchase agreement concerning generators for a power plant, sited in Stockholm. Also represented the same client in related court litigation proceedings in the District Court of Helsinki concerning a claim for unjust enrichment brought by the parent company of the same opponent.

As a lead counsel successfully acting for a long-standing Finnish manufacturer in potential FAI and LCIA arbitration proceedings against several European subsidiaries of a Chinese long-established manufacturing company, arising from the parties’ joint infrastructure projects in several European locations, governed by both Finnish and English law. Secured a highly favourable settlement of the dispute;

Successfully advising and acting for a major European manufacturer in a multimillion-euro international ad hoc arbitration concerning the supply of a production line to a Finnish Company, seated in Helsinki;

As a co-lead counsel, successfully advising and acting for a Finnish subsidiary of a leading global technology company in an International Ad Hoc Arbitration dispute arising from a purchase contract relating to a large construction project in the Middle East, seated in Helsinki.

Heidi accepts instructions in disputes arising in the telecommunications field and has been involved in numerous high-value, complex and multi-jurisdictional disputes.

Recent work includes:

Acting as a Finnish co-counsel for a leading global IT services company in ICC arbitration proceedings against a major Nordic telecommunications company, seated in Helsinki and governed by Finnish law, arising from services agreements in the telecommunications field.

Advising a leading Nordic publicly listed telecommunications company in potential ICC arbitration proceedings, seated in Helsinki and governed by Finnish law, arising from a joint-venture agreement in the technology sector.

Successfully advising and acting for an international media company in a multi-million-euro International Arbitration dispute arising from a joint venture agreement in the telecommunications field, governed by the DIS Rules, seated in Munich.

Heidi accepts instructions in disputes arising in the shipping, transport and logistics sectors and has been involved in numerous high-value, complex and multi-jurisdictional disputes.

Recent work includes:

Representing an international seafood company and charterers in four separate multi-million LMAA arbitration proceedings (heard concurrently) concerning the performance of long-term charterparties for the carriage of fish, seated in London and governed by English law.

As a co-lead counsel advising and representing several global insurance companies and owners of oil and chemical tankers, flagged in Malta, against a leading global provider of marine and energy solutions and services in a multi-million-euro maritime dispute in the District Court of Pohjanmaa, concerning the supply of unfit propulsion systems to the tankers.

Acted as a lead counsel for a Dutch seller of luxury yachts in litigation proceedings in the District Court of Helsinki against a Finnish purchaser. Secured a favourable judgment for the client.

As a co-lead counsel, successfully advising a leading global bio and forest products company in potential FAI arbitration proceedings against a Finnish subsidiary of a leading multinational shipping and logistics company arising from a long-term logistics agreement, governed by Finnish law, seated in Helsinki. Secured a favourable settlement of the dispute.

Further information

Legal500 Arbitration Private Practice Powerlist UK 2022 and 2023, Leading Arbitration Counsels in the UK

Who’s Who Legal Arbitration – Future Leaders 2018-2024

Finnish Bar Association’s scholarship to study LLM at Queen Mary University of London

City, University of London, Law Department prize for overall high exam results (November 2001);

City, University of London, Law Department prize for the best company law exam result (November 2003)

Appointments & Memberships

Called to the Bar in England and Wales (Honourable Society of Inner Temple),

Non-practising Solicitor (Solicitors Regulation Authority, Law Society of England and Wales)

Attorney (asianajaja) in Finland, the Finnish Bar Association

The Chartered Institute of Arbitrators, fellow

The Commercial Bar Association (COMBAR)

Arbitral Women

The LCIA

The Finnish Arbitration Association

Young Arbitrators Stockholm

The Scottish Arbitration Centre

Working languages: English and Finnish.

Intermediate level: Swedish, Turkish, German