John D. Renneisen

Senior Counsel

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John D. Renneisen provides legal advice on environmental issues in the context of mergers and acquisitions (M&A), debt and equity financing, and compliance counseling. His practice spans the spectrum of environmental matters at the federal, state, and local levels, including transactional due diligence and contract negotiation, hazardous waste management, hazardous site remediation, water pollution, air pollution, and toxic substance regulation. John also conducts property and compliance diligence, drafts and negotiates transaction agreements, and monitors project progress in connection with asset purchases, underwritings, securitizations, leases, and sale-leaseback transactions.

Drawing on his technical background and knowledge of environmental law, John helps clients identify problems and craft effective solutions. On transactional matters, he remains focused on the overall size and structure of the deal in order to help resolve material issues in the most efficient manner. John represents institutional and private equity investors with interests and portfolio companies in a range of industries, including oil and gas exploration and production and renewable electricity generation. In addition to his work in conventional and alternative energy, he has experience in pharmaceuticals, biotechnology and other industrial, manufacturing and commercial sectors.



Bar Admissions

  • District of Columbia


  • Duke University, J.D., 1993
  • Massachusetts Institute of Technology, M.S., Mechanical Engineering, 1988
  • Williams College, B.A., Mathematics and Physics, 1986

Professional Activities


  • Hydraulic Fracturing Developments,” Pratt’s Energy Law Report (January 2017)
  • Hydraulic Fracturing Developments,” Pratt’s Energy Law Report (June 2016)
  • Hydraulic Fracturing Developments,” Pratt’s Energy Law Report (March 2016)
  • “New Cleanup Obligations for EU Industrial Facilities,” Law360, co-authored with Eric Rothenberg, (November 12, 2015)
  • “Regulatory Risk and Financing: Perspectives on Transactional Due Diligence,” American Wind Energy Association (AWEA) Wind Project Siting Seminar (2012)
  • Represented Constellium NV (an Apollo Management portfolio company) in its acquisition of Wise Metals Group LLC for US$1.4 billion in October 2014.
  • Represented Apollo Management in its acquisition of OM Group, Inc., for US$1 billion in August 2015.
  • Represented Apollo Global Management and its portfolio company, Taminco Corp. (Taminco), the world's largest producer of alkylamines and alkylamine derivatives, in the US$2.8 billion sale of Taminco to Eastman Chemical Company, a global producer of specialty chemicals. 
  • Represented equity investors in multiple utility-scale wind energy developments.
  • Handled the environmental due diligence and transaction documentation issues for electric power generation projects worth more than US$15 billion, including independent power production and cogeneration projects, and coal, oil, natural gas, geothermal, hydroelectric, wind, solar, and biomass generation.

In the News

Press Releases

Alerts and Publications

EPA Proposes New Greenhouse Gas Emissions Standards for Fossil Fuel-Fired Power Plants

May 23, 2023

Mining Company Agrees to Pay US$56 Million to Settle SEC ESG Disclosure Suit

March 31, 2023

EU to Impose Carbon Border Tax on Imported Products

January 10, 2023

Environmental Justice Update (October 2022)

October 17, 2022

Inflation Reduction Act Adds First-time Charge for Methane Emissions for the Oil and Gas Sector

August 16, 2022

Department of Justice Launches Comprehensive Environmental Justice Strategy

May 9, 2022

FERC Issues Pause in Natural Gas Pipeline Policy Statements as the White House Announces an Initiative for Increasing LNG Exports to Europe and the D.C. Court of Appeals Provides Guidance on Consideration of Greenhouse Gas Emissions

March 25, 2022

FERC Issues New Policies for Review of Applications for New and Modified Natural Gas Pipelines, Including Consideration of Greenhouse Gas Emissions for Pipeline and LNG Facilities

February 22, 2022