Athena Economics was founded by Guillaume Madelpuech, an economist and transfer pricing specialist with over 18 years of experience across the full transfer pricing lifecycle — from policy design and economic analysis to audit defence and controversy management.

Guillaume began his career at EY, working across the Paris and New York transfer pricing practices, before joining NERA Economic Consulting as a Principal, where he led complex economic analysis mandates for multinational corporations — including high-profile EU Commission proceedings. He subsequently held Director positions at KPMG and Forvis Mazars, where he acted as trusted adviser and de facto outsourced Head of Transfer Pricing for several major multinational groups across Europe.

His work spans a broad range of industries — including financial services, technology, industrials and energy — and covers over 30 jurisdictions. He holds degrees from ENSAE, Paris Dauphine University (Master's in Industrial Economics) and ESSEC Business School.

Guillaume is based in Paris and works with clients across jurisdictions.