Sean Marciniak

Sean R. Marciniak


  • Print Page
  • Email Page
  • Share this page
Land Use
Land Use
East Bay

Sean is a Partner in Hanson Bridgett's Land Use Practice Group. He represents public agencies, landowners, and developers on a number of environmental and land use matters, focusing on counseling under the California Environmental Quality Act, Planning and Zoning Law, and Subdivision Map Act. His creative and efficient approach to problem solving has helped entitle millions of square feet of development in California, including mixed-use development, regional hospitals, laboratories, shopping centers, office campuses, infrastructure projects, terminal expansions and intermodal transport facilities at California’s busiest ports, and solar energy projects.

Sean is also proficient in the National Environmental Policy Act, takings and exactions, development agreements, initiatives and referendums, Local Agency Formation Commissions, affordable housing, the Subdivision Map Act, natural resource permitting (including under the Endangered Species Act and Clean Water Act Sections 401 and 404), and emerging laws addressing climate change and sustainable development.

In the past, Sean has litigated land use issues in superior and appellate courts across the state, as well as the California Supreme Court. This experience enables him to see (and resolve) problems that competitors cannot.

Prior to joining Hanson Bridgett, Sean was a shareholder at Miller Starr Regalia, where he helped write and edit sections of land use practice guides including Miller & Starr, California Real Estate 4th, a 12-volume treatise on California real estate law. He began his legal career in the environmental and land use practice at an international law firm where he edited and wrote sections of other land use treatises and practice guides used across the state.


The End of the Line for Exclusionary Zoning: Berkeley Set to Make its Move, Land Use Law Alert (February 2021)

"CEQ Final Rule for Federal Agencies Implementing NEPA," Land Use Law Alert (July 2020)

"CEQA Reform in the COVID Era? The California Senate Housing Production Package Moves Forward," co-author, Land Use Law Alert (June 2020)

"Court Clarifies Mitigation Needs for Buried Artifacts, Plants, and Trees," Land Use Law Alert (April 2020)

"Construction to Continue For Now Following Governor Newsom’s "Stay at Home" Order," co-author, Construction + Government Law Alert (March 2020)

"Updates to CEQA Technical Advisories on Disaster Response and Housing," co-author, Land Use Alert (January 2020)

"The Case Against Formula Retail Ordinances: Understanding the Problem and Crafting Solutions," co-author, Shopping Center Law & Strategy (October 2017)

"American Tower Corporation v. City of San Diego (2014): Further Guidance From The Ninth Circuit On The Regulation Of Data Towers In California," Miller Starr Regalia Legal Update (December 2014)

"Local Matter or Federal Case? The Network of Cell Tower Regulation in California," co-author, California Real Estate Newsalert, Vol. 21, No. 6 (July 2011)

"Back to Basics: Setting the Environmental Baseline Under the California Environmental Quality Act," co-author, California Land Use Law & Policy Reporter (February 2011)

"NEPA Review and Impacts on Climate Change" (March 2008)

See All Publications


"Midsize and Boutique Law Firm Panel," panelist, Berkeley Law (September 2017)

"Practice Area Table Talks," panelist, Berkeley Law (November 2016)

“Infill Development: Critical Paths & Strategic Entitlement Roadmaps,” Miller Starr Regalia (January 2012)

“Development Opportunities in Uncertain Times,” Miller Starr Regalia (January 2011)

“Keeping Bay Projects Moving,” Bay Planning Coalition Workshop Series (2010)

“Central California Annual Land Use & Planning Conference,” Lex and the City (April 2009)

See All Presentations


Rising Star, Super Lawyers Northern California (2012-2017)

Professional Affiliations

American Bar Association

Bay Planning Coalition, Former Board Member

Contra Costa County Bar Association

Urban Land Institute


J.D., University of California, Berkeley School of Law (2007)

M.A., University of California Graduate School of Journalism (2004)

B.A., Brandeis University (1999)

Admissions And Courts




East Bay

(925) 746-8471 Direct Phone
(925) 746-8490 Fax

Email Attorney


Firm Leadership

Land Use Practice Leader