
Energy
Infrastructure
Project Development
Jonathan Castelan is a partner at Clifford Chance in Houston, where he co-heads the Energy Transition Group. With a focus on energy and infrastructure transactions, Jonathan has extensive experience in the energy sector, including traditional oil and gas, energy infrastructure, and energy transition projects. He advises on carbon capture, utilization, and sequestration (CCUS) projects, hydrogen projects, and renewable fuel initiatives. Jonathan's expertise extends to construction-related contracts, purchase and sale documentation, and joint ventures. He holds a JD from The University of Texas School of Law and a BA from Southern Methodist University.
Energy and Infrastructure Development
Renewable and Alternative Energy
Financial Services and Investments
Commercial and Strategic Transactions

- ExxonMobil entered into a CO2 Transportation and Storage Agreement with Fidelis on a date not available. - Deal value was 2900000000 Sector: Energy; Location: USA. - On the acquirer side, counsel was not available; lawyers included David Stringer, Jonathan Castelan.
Oct 08 2025
3B
M&A

Partner
2023 – Unknown
Partner
2019 – 2023

Partner
2017 – 2019

- Exxon Mobil Oil Company acquired the target/assets from Superior Graphite in a acquisition on not available. - Deal value was 3100000000 Sector: Energy; Location: USA. - On the acquirer side, not available advised, led by Chang-Do Gong, Jonathan Castelan, Paul Koppel, Philip Wagman, Ty'Meka Reeves-Sobers, Violetta Kokolus.
Sep 12 2025
3B
M&A
TotalEnergies (NYSE:TTE) has announced it has signed a definitive agreement with SunPower Corp.’s (NASDAQ:SPWR) to purchase its Commercial & Industrial Solutions (CIS) business for US$250 million, including US$60 million of earn-out subject to regulatory evolution. TotalEnergies is the majority shareholder of SunPower, a leading solar technology and energy services provider. Latham & Watkins LLP represents TotalEnergies in the transaction with a corporate deal team led by Houston partner Ryan Maierson, with Houston associates Denny Lee, Jordan Mack, Zainab Hashmi, Ziyad Barghouthy, Morgen Seim, and Corynn Wilson. Advice was also provided on tax matters by Houston partners Tim Fenn and Jim Cole, with Houston associate Mike Rowe; on benefits and compensation matters by Washington, D.C. partner Adam Kestenbaum and Washington, D.C. counsel Laura Szarmach; on antitrust matters by Washington, D.C. partner Jason Cruise, Frankfurt partner Max Hauser and Washington, D.C. counsel Sydney Smith; on FCPA matters by London partner Nathan Seltzer and Washington, D.C. partner Erin Brown Jones, with Boston associate Matthew Crawford; on sanctions matters by Washington, D.C. partner Jim Barker and London partner Charles Claypoole, with London associate Amaryllis Bernitsa; on FERC matters by Washington, D.C. partner Tyler Brown; on data privacy and security matters by Bay Area counsel Robert Blamires, with San Diego associate Kathryn Parsons-Reponte and Bay Area associate Adriana Beach; on real estate matters by San Diego partner Robert Frances and San Diego counsel Aaron Friberg; on intellectual property matters by Orange County counsel David Kuiper, with Century City associate Nathan Wages; on commercial due diligence by Houston partner Jonathan Castelan, with Houston associates Tom Hillebrand and Vera Bespalova; and on environmental matters by Los Angeles counsel Josh Marnitz.~~
Feb 10
1 min
Energy Section
2014 – 2017
Corporate Counsel
2011 – 2014
Legal Counsel
2009 – 2011
Counsel – Operations & Compliance
2006 – 2009