Mark F. Sundback


Straight Talk® is good business



Contact Information

Washington, DC

1350 I Street, NW
Suite 1100
Washington, DC 20005
P: +1.202.662.2755
F: +1.202.662.2739

Mark F. Sundback


Washington, DC Office
1350 I Street, NW
Suite 1100
Washington, DC 20005
P: +1.202.662.2755
F: +1.202.662.2739

Mark is a Partner in the Energy section of the Washington, DC office. Since 1981 he has been extensively engaged in the representation of energy industry participants before federal and state agencies charged with jurisdiction over energy markets and their participants. His representations have focused on the rates, terms and conditions associated with gaining access to regulated energy transmission systems, transactions involving changes in ownership of jurisdictional assets and unbundling matters.

Particularly, Mark’s practice includes a wide array of issues under the Natural Gas Act, the Federal Power Act and related federal and state statutes involving the regulation of energy industry participants. He has been involved in counseling and representing before the Federal Energy Regulatory Commission multiple merchants of electric power in the Southeast United States and New England. He is defending entities in the Pacific Northwest that have been accused of charging rates for electricity and capacity inconsistent with the standards of the FPA. He also has appeared before the regulatory commissions of numerous states on behalf of end users and coalitions of market participants.

His work frequently requires the integration of both transactional and regulatory goals. Over the past three years, Mark has forged durable, commercially-resilient agreements to transactional and regulatory disputes arising between energy market participants. Some of the disputes had been underway for 10 years before resolution. In like fashion, Mark has addressed commercial challenges in negotiating arrangements for new projects, allocating capacity, and designing and implementing open seasons with creative, commercially-viable solutions.

Representative Experience


  • Served in first chair capacity involving on the record cases for pipelines in over a dozen NGA Section 4 proceedings involving rates, and has represented other market participants in rate cases as well
  • Has counseled and litigated cases involving innovative pipeline project transactions, including interconnection disputes, contested certificate matters, issues arising from pipeline facilities shared by two pipelines and financing
  • Litigated seminal cases involving application of the Outer Continental Shelf Lands Act to oil and natural gas pipelines      


  • Successfully represented entities engaged in generation and marketing against ISO claims in arbitration
  • Involved in Commission proceedings in numerous states, including California, Pennsylvania, Texas, Florida and Maryland
  • Served as chief energy regulatory counsel in numerous bankruptcy proceedings, including for bankrupt electric generators and their creditors
  • International energy arbitrations involving pricing of natural gas supplies and power plant fuels

Pipelines & Electric

  • Reorganizations/restructuring of regulated energy enterprises



Professional Recognition






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