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Press Release

Keller and Heckman Continues Expansion with Addition of Partner Sophie Castillo to the Proposition 65 and Litigation Practices in the San Francisco Office

—San Francisco— International regulatory law firm Keller and Heckman LLP continues to expand with the strategic addition of Partner Sophia (Sophie) Castillo in the firm’s San Francisco office, focusing on California’s Proposition 65 and Litigation, as well as regulatory advice on emerging chemicals and contaminants, particularly in California.

Sophie has extensive experience counseling clients throughout the entire supply chain (importers, manufacturers, distributors, and retailers) on compliance, litigation, and risk avoidance surrounding California’s Proposition 65, as well as other state and national laws related to chemicals and toxics. She also advises clients regarding state laws and regulations related to emerging contaminants, including PFAS, in the food, cosmetics, textiles, and consumer products industries.

Partner Mitzi Clark, who manages the San Francisco office, expressed her enthusiasm to expand the firm’s Proposition 65 and Litigation teams. “California has one of the most stringent regulatory climates in the country, so Sophie’s vast experience handling matters related to California’s regulations across the supply chain provides our practice with a tremendous competitive advantage. We are excited to introduce her to our clients.”

Sophie is one of several recent additions to Keller and Heckman’s legal team. Since April, the firm welcomed Partners Katie Bond and David Joy, as well as experienced Associate Samuel Butler. These talented additions demonstrate the firm’s commitment to excellence in legal services and the desire to continuously evolve and keep up-to-date with industry advancements and regulations.

“It is exciting for me to have the opportunity to join a team of attorneys and scientists who are well-respected across the globe. The firm’s collaborative and holistic approach to legal matters especially with regard to litigation and evolving regulations is well-known within the legal industry,” reflected Sophie. “I developed my practice on these same principles because it is imperative to keep clients apprised of the constantly changing regulations surrounding chemicals, toxics, and emerging contaminants; therefore, I knew joining Keller and Heckman was a natural career move.”

Sophie received her J.D. from University of California, Hastings College of Law, and her B.A. from University of California, Los Angeles.

About Keller and Heckman

Keller and Heckman LLP represents a wide spectrum of companies and trade associations servicing a range of industries, including advertising and labeling, food and food additives, plastics, pesticides, industrial and specialty chemicals, consumer products, drugs and medical devices, transportation, and telecommunications. The firm's practice covers the diverse regulatory areas that affect these industries, as well as public policy and litigation matters. Our attorneys and scientists emphasize creative service to clients involved in the development of new products, services, and markets. Our attorneys and staff serve clients from offices in Washington, DC, Brussels, San Francisco, Shanghai, and Boulder.