Mark S. Lester

Professional Liability and Trial Practice

Mark S. Lester, Managing Partner

Mark Lester is recognized as one of the premier professional liability and general civil trial lawyers in Southern California. With over 20 years of big law firm experience before starting Lester & Cantrell, he has handled cases for clients ranging from Fortune 100 companies to local small business and professional service firms.

He is AV-Preeminent rated and an experienced trial lawyer with membership in American Board of Trial Advocates (ABOTA). He is also one of the very few attorneys in California who has been certified as a specialist in Legal Malpractice Law by The State Bar of California Board of Legal Specialization.

Representation of Professionals

Mark devotes a substantial portion of his practice to the representation of attorneys, law firms and other professionals in claims based upon theories of malpractice, breach of fiduciary duty, fraud and misrepresentation, breach of contract, unfair business practices and others. He has tried both jury and non-jury matters for sole practitioners and large law firms and other professional service firms. Additionally, he has conducted binding contractual arbitrations of such disputes and participated in countless mediations and other negotiations of such claims both before and after commencement of litigation. From time to time, Mark also provides consultation and expert testimony with respect to professional responsibility, standard of care and reasonable fee issues pertaining to attorneys. He has testified at numerous arbitrations and trial proceedings.

General Civil Practice

Mark also handles matters involving private business, industry and individuals in commercial, corporate and real estate matters; property and casualty claims; landowners and operators; product liability matters; and construction related claims in both public and private works of improvement. He has tried cases in many California counties as well as outside the state.

Certified Legal Specialties

Legal Malpractice Law, California Board of Legal Specialization of the State Bar of CA, 2011

Bar Admissions

U.S. District Court Central District of California
U.S. District Court Southern District of California


University of San Diego School of Law, San Diego, California J.D.
Law Review: Member, 1984 – 1985

University of California, San Diego, California (B.A. – 1982)
Major: English/American Literature

Representative Clients

Lawyers and Law Firms
Corporations and other Business Entities

Classes and Seminars

Top Ten Legal Malpractice Mistakes, Provisors, 2014 – Present
Twenty Quick Tips to Avoid E&O Claims, Ahern Insurance Brokers, 2013 – Present

Honors and Awards

AV-Preeminent Rated

Professional Associations and Memberships

American Board of Trial Advocates (ABOTA), Associate member, 2005 – Present
ABA Lawyers Professional Liability Consortium , Member, 2011 – Present
State Bar of California, Committee on Professional Liability Insurance – Member – 2004 to 2011
Association of Southern California Defense Counsel – Member 1988 – 2006; Board Member 2003 – 2005
Riverside County Bar Association – Member – 1994 – Present
San Bernardino County Bar Association – Member – 2010 – Present

Past Employment

Haight, Brown & Bonesteel LLP, Associate/Partner, 1985 – 2006
Lobb Cliff & Lester LLP, Partner, 2006 – 2010

Pro Bono Activities

Public Counsel, 1988 – 1993

Areas of Practice

  • Professional Liability Claims 50%
  • Commercial, Corporate and Real Estate 30%
  • General Civil Litigation and Trials 20%

Where to Find Us

Riverside Office

Newport Beach Office

Riverside Office: 1700 Iowa Ave Suite 200, Riverside, CA 92507. Get Directions.

Newport Beach Office: 3101 West Coast Highway, Suite 307, Newport Beach, CA 92663. Get Directions.