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Sigourney R. Haylock

Counsel | She/Her/Hers

Overview

Sigourney is a litigator who focuses her practice on defending companies in high-stakes commercial litigation. She has particular experience representing clients in the retail and consumer products, food and beverage, real estate, and healthcare sectors.

Sigourney represents clients in a range of complex commercial litigation matters, including false advertising, unfair competition, consumer class actions, product liability, and business and contract disputes. She also counsels clients regarding Proposition 65 compliance, pre-suit notices and threatened litigation.

In her real estate practice, Sigourney regularly advises clients on lease interpretation issues such as abatement, defaults, co-tenancy, force majeure and maintenance obligations. She understands the operational and financial pressures legal disputes can create and works closely with clients to develop strategies aligned with their business objectives.

In 2021, Sigourney was recognized as a "Top 40 under 40" lawyer by The National Black Lawyers, an organization that recognizes lawyers who have a reputation for providing excellent legal representation and who are leaders in their respective practice areas.

While in law school, Sigourney served as a Note and Comment Editor for the Loyola of Los Angeles Law Review and as a certified advocate in Loyola’s Youth Justice Education Clinic. She also externed for the Honorable André Birotte, Jr. in the U.S. District Court of the Central District of California.

Career & Education

    • University of California, Santa Barbara, B.A., Environmental Studies, Minor in Global Peace and Security, 2012
    • Loyola Law School, Los Angeles, J.D., 2017
    • University of California, Santa Barbara, B.A., Environmental Studies, Minor in Global Peace and Security, 2012
    • Loyola Law School, Los Angeles, J.D., 2017
    • California
    • U.S. District Court for the Central District of California
    • California
    • U.S. District Court for the Central District of California

Sigourney's Insights

Firm News | 1 min read | 10.29.25

Crowell Secures Victory for Mondelēz in False Advertising Alleged “Greenwashing” Suit

Chicago – October 29, 2025: Crowell & Moring secured a complete dismissal with prejudice of a proposed class action suit on behalf of Mondelēz, LLC in the Northern District of Illinois....

Representative Matters

  • Defeated consumer class action filed against a snacking company in N.D. Ill. alleging false advertising and greenwashing over “climate neutral certified” labeling on a food company’s brand of snack bars. All claims were dismissed with prejudice, with the judge agreeing the truthful certification statement was non-deceptive and plaintiff faced no risk of future harm.
  • Represented a bakery-café against false advertising claims (clean), resulting in two successful motions to dismiss and a positive resolution.
  • Represented manufacturer of personal care products in multi-plaintiff suit regarding consumer complaints of skin irritation, hair thinning, and hair loss resulting in dismissal.
  • Defended a fashion retailer in litigation regarding co-tenancy and lease termination issues, resulting in a favorable settlement at mediation.
  • Counseled companies whose products were alleged to contain various Proposition 65-listed chemicals on regulatory compliance and threatened litigation.
  • Assisted in Prop 65 compliance counselling and violation notice investigations for companies whose products were alleged to contain various listed chemicals including lead and lead compounds, mercury, acrylamide, hexavalent chromium, DEHP and DINP.
  • Represented a medical device manufacturer in mass tort federal and state products liability suits alleging design and warnings defects, fraud, and breach of warranties.

Sigourney's Insights

Firm News | 1 min read | 10.29.25

Crowell Secures Victory for Mondelēz in False Advertising Alleged “Greenwashing” Suit

Chicago – October 29, 2025: Crowell & Moring secured a complete dismissal with prejudice of a proposed class action suit on behalf of Mondelēz, LLC in the Northern District of Illinois....

Sigourney's Insights

Firm News | 1 min read | 10.29.25

Crowell Secures Victory for Mondelēz in False Advertising Alleged “Greenwashing” Suit

Chicago – October 29, 2025: Crowell & Moring secured a complete dismissal with prejudice of a proposed class action suit on behalf of Mondelēz, LLC in the Northern District of Illinois....