Pinsent Masons has hired a partner from London arbitration boutique Volterra Fietta to co-head its investor-state dispute settlement and public international law team.

Graham Coop has joined the firm in London after almost 10 years at Volterra and will lead the team alongside Sylvia Tonova, who herself joined Pinsents earlier this month from Jones Day. 

Coop brings experience representing states, companies and international organisations on investment and commercial arbitrations and other public international law matters, including state-to-state and sovereign immunity issues. 

During his time at Volterra, Coop represented clients under all the major arbitration rules with a focus on the energy and financial markets. He has advised sovereign clients and energy companies on matters including public international law, competition and regulatory issues, major projects, project finance, banking, joint ventures, and supply, transport and regasification agreements. 

Before joining the firm he also served for several years as general counsel to the Energy Charter Secretariat in Brussels.

Coop is the third investor-state arbitration and public international law partner to join Pinsents this year, the firm having also added Amaia Rivas Kortazar in Madrid earlier this year to lead its local public law offering. 

London partner Jason Hambury, global co-head of Pinsent Masons’ international arbitration practice, said: “Graham is recognised as one of the leading experts on international energy law, the Energy Charter Treaty and investment treaty arbitration. He will play a significant role in the continued success of our practice and we are delighted to welcome him.”

He added that the hire of Coop, Tonova and Rivas Kortazar underscored the firm’s commitment “to support our clients who are continuing to face uncertain geopolitical developments and challenges around meeting their net zero commitments, as well increasing regulatory burdens in an ever-changing investment environment in their respective markets.”

Coop’s focus on energy dovetails nicely with Pinsents’ international arbitration team, which is known for its energy and infrastructure-related expertise. Hambury leads the practice, which also acts in commercial arbitrations involving project-related joint ventures as well as the aerospace, tech, manufacturing, pharmaceutical, IP and banking and finance sectors, alongside Hong Kong partner Dr Dean Lewis. 

Coop’s departure leaves Volterra with four partners, according to its website, including leading public international law specialist and name partner Robert Volterra.