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Ariane Mahler

Chief Investment Officer & Portfolio Manager

Ariane Mahler is CIO/CEO of Veridien Global Investors and lead portfolio manager and analyst, focusing much of her time on the energy, utility, mining and technology sectors. She oversaw approximately $10 billion at the peak in assets under management.

While her studies of French mathematician Joseph Fourier and Swedish 1903 Nobel prize physicist and chemist Svante Arrhenius sparked her interest in climate change early on, it was her increasing understanding of environmental issues and her concern for the future of our planet that guided her focus throughout her investment career. In 2015, she launched Carbon Zero, the most ambitious emission reduction fund of its kind for La Française Asset Management. In 2018, she started the Climate Action Strategy, with a dual purpose of delivering exceptional risk adjusted returns, while helping drive energy efficiency and global decarbonization.

Ariane’s career began as an analyst at SG Warburg and finance officer at Bear Stearns. Subsequently, she spent 21 years as a lead or co-lead portfolio manager on global equity and sector focused equity portfolios, the majority of which was spent alongside the former CIO and President of Oppenheimer Capital International (at Oppenheimer and the France Growth Fund) and the former CIO of Tradewinds Global Investors (at Tradewinds and Kopernik Global Investors*). Other portfolio management and analytical experience was at Dresdner Kleinwort Wasserstein, Credit Suisse Asset Management, and La Française. 


Ariane holds a M.S. in Finance from the London School of Economics studying Capital Market Theory under Mervyn King, and a B.A. in Economics, ESSEC (Ecole Supérieure des Sciences Economiques et Commerciales.

*Analyst Consultant for Kopernik Global Investors

  • Ariane Mahler

Barney Walker


Barney Walker is a Principal at Veridien.  He is responsible for developing and managing partnerships in North America, Europe and the Middle East.  


Prior to co-founding the firm, Mr. Walker was co-head of global distribution at Strategic Global Advisors. Previously, he was a Partner at Aligned Asset Managers LLC, a portfolio holding company of GTCR, LLC where they provided growth equity capital and distribution expertise to their member firms. Previously, Mr. Walker was a Senior Vice President at Artio Global Investors, LLC (f/k/a Julius Baer Investment Management, LLC) where he shared leadership for new business and client service from 2002-2012, helping grow the firm to approximately $80 billion.

Mr. Walker started his career at Ark Asset Management, Inc. where he worked from 1996-2002 holding various institutional new business/client service roles after spending two years as a junior member of the portfolio team. He earned his BS from Boston College. 

  • Barney Walker

Paulus Ingram

Head of Impact &. Engagement

Paulus Ingram is Head of Impact and CCO at Veridien Global Investors. Paulus started working with Ariane as an advisor in the development of the Climate Action Strategy in 2018. 

Paulus has served as a Senior Advisor to the impact-focused Capricorn Investment Group, a $10 billion multi-family office anchored by Jeff Skoll and the Skoll Foundation. He also served as Investment Committee Chair for the Sarona Global Growth Markets PE Fund 2 (mid-market emerging markets private equity impact fund of funds) and as Investment Committee Member for the Secured Accial Impact Lending Fund (impact-focused, tech-enabled investment in fintech lending portfolios in emerging markets). Paulus has advised multinational corporate investors on carbon capture and renewable energy projects in the United States.

Previously, Paulus was Head of Hedge Fund Investments at Dutch pension asset manager APG, responsible for a $23B hedge fund program (2009-2016) managed out of New York and Amsterdam. At APG, Paulus had been Senior Portfolio Manager Head Funds, Senior Portfolio Manager Opportunity Fund  worked with the Sustainability and Governance team to establish thought leadership and action for the $500 billion portfolio on climate and impact. 

Paulus is a CAIA charter holder, member the CFA Society of the UK (IMC) and holds a Master of Laws from Vrije University in the Netherlands, Masters in International Finance from University of Amsterdam, B.As in Biology and English Literature from Amherst College and a certificate from Oxford University’s Said School of Business Private Equity Program.

  • Paulus Ingram

John Dewey


John Dewey is a Managing Principal at Veridien Capital Partners.  He is responsible for developing and managing new partnerships in North America, Latin America and Asia. 

Prior to co-founding the firm, Mr. Dewey was co-head of global distribution at Strategic Global Advisors, tripling firm assets over a four-year period. Previously, he led Australia-based Magellan Financial Group’s North American business development and client service helping drive asset growth to over $100B. Mr. Dewey’s prior experience also includes serving as a product specialist while at PIMCO, and numerous roles at Capital Guardian Trust Company, including the launch of the firm’s middle market business. Mr. Dewey's previous experience includes serving as treasurer for a publicly traded leasing company and direct lender to venture capital backed technology and life science companies.  Mr. Dewey earned an MBA from Santa Clara University and a BA from University of California, Los Angeles.

  • John Dewey
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