Sheila Sonenshine

Hon. Sheila Prell Sonenshine (Ret.)

Case Manager
Lisa Abrantes
T: 619-237-0801
F: 619-236-9032
5 Park Plaza, Suite 400, Irvine, CA 92614


Spanning over four decades as lawyer, Judge, Justice, and JAMS mediator/arbitrator, Hon. Sheila Prell Sonenshine has embraced the challenges of emotionally charged disputes and brought them to successful resolution.

As an attorney she played an instrumental role in the development of a computerized estate planning program for a prominent Wall Street brokerage firm while working effectively with its high net worth clients. Her estate planning practice also included consulting with families of Western Regional Center patients, the drafting of pre-marital agreements, and providing legal advice on conservatorships as well as estate, trust, and probate litigation.

Justice Sonenshine wrote scores of opinions in matters involving wills, trusts, and intestacy in her nearly twenty years on the bench. She also resolved hundreds of cases at settlement conferences, including 85% of those that she heard under the appellate settlement conference program she inaugurated.

Justice Sonenshine founded and served as Managing Director of an international investment banking firm (M&A) focused on privately held mid market businesses. This experience makes her particularly adept in resolving closely held family business disputes.

As a mediator she is sensitive to the personal nuances involved in estate, probate, and trust litigation. She is known for patiently working to bring the parties together and for her common sense approach to resolving disputes.

As an arbitrator, her command of the process, demonstrated fairness, and knowledge of the law and rules result in appropriate, timely, and well-reasoned awards.


  • ADR
    • Handles cases ranging in size from smaller, private family law matters to large three-panel arbitrations involving international parties
    • Her intimate knowledge of the appellate process makes her a trusted trial strategy consultant
    • Efficiently administers neutral evaluations, mock trials, appellate review, and mediations and arbitrations for appellate-level matters
    • Respected by clients for possessing a real world, analytical, and practical understanding of difficult issues and the ability to resolve them
  • Legal and Judicial
    • One of four original justices appointed to the Fourth District Court of Appeal, Division Three, serving 17 years
    • One of the youngest appointments to the California Superior Court and Court of Appeal
    • Established a successful law practice out of law school utilizing trial, negotiation, and settlement skills
    • As an attorney, E.F. Hutton retained her to aid in its development of computerized personal finance programs. Justice Sonenshine also served as an advisor to E.F. Hutton’s high net worth clients
  • Business
    • Founded and served as Managing Director of an international investment banking (M&A) firm sold to H&R Block following a successful career on the bench
    • Founded a nationally chartered federal bank later sold to Wells Fargo Bank
    • Formed Sonenshine Enterprises, which invested in a number of women-led companies and served as a trusted advisor to numerous female entrepreneurs


Representative Matters

  • Will contests
  • Trust property
    • Action for prejudgment trust property attachment (Kadison, Pfaelzer, Woodward, Quinn & Rossi v. Wilson (1987) 197 CA 3d 1)
  • Nondonative transfers
    • Probate Code section 21225 and nondonative transfers of an option to renew, right of first refusal, and a lease commencing at a certain time (Shaver v. Clanton (1994) 26 CA 4th 568)
  • Children/stepchildren claims 
    • Children of a decedent’s predeceased spouse claimed an interest in his estate, alleging as step children they were the closest heirs (Estate of Claffey (1989) 209 CA 3d 254)
    • Creditor claim against son of decedent’s mother’s estate and claim of fraudulent conveyance of joint tenancy conveyance (Estate of Baumann (1988) 201 CA 3d 927)
    • Determination of son’s heir ship in birth father’s intestate estate where step father previously adopted son and out of state court affirmed its validity (Estate of Hart (1984) 165 CA 3d 392)
    • Adopted child’s right to inherit from intestate natural parent
  • Trustee bond
    • Trustee required to post bond when appointee was not designated
    • Bond not required when executor is named as trustee and trust does not require bond and unnecessary to protect other beneficiaries and they waived bond; beneficiary’s cannot require and no creditors need protection (Cibulk v. Cibulk (1998) 67 CA 4th 690)
  • Disputes between prior and widowed spouses 
    • Former spouse’s right as designated beneficiary to proceeds from decedent’s employment savings plan (Snyder v. Snyder (1987) 197 CA 3d 6)
    • Former spouses' rights to undivided life insurance proceeds as designated beneficiaries
  • Terminable interest rule
    • Inapt to nonrestrictive beneficiary choice in private pension (Bowman v. Bowman (1985) 171 CA 3d 148)
  • Community Property
    • Community property interest in life insurance policy partially funded with community property (Bowman v. Bowman (1985) 171 CA 3d 148
  • Joint Tenancy Property
    • Action between decedent’s mother and widow over joint tenancy family residence (Byrd v. Blanton (1983) 149 CA 3d 987)
  • Creditor Claims
    • Decedent’s business creditor sought widow’s personal liability for estate’s insolvency (Estate of Davis (1990) 219 CA 3d 663)
  • Dispute between family members over buy sell, succession planning, and company value and pay out

Bar Associations, Affiliates and Other Professional and Pro Bono Groups

  • Recipient of the Project Youth OCBF Volunteer Excellence Award, Project Youth Orange County Bar Foundation, 2019
  • Named one of Loyola Law School's 50 Inspirational Alumni, 2014
  • First recipient of Justice David G. Sills Award for Appellate Excellence, Orange County Bar Association Appellate Law Section, 2011
  • Robert Samuel Barnes Award, Orange County Bar Foundation, 2006
  • Marcus Kaugman Jurisprudence Award, Anti-Defamation League, 2004
  • Founder and Chair, Sonenshine Pro Bono Reception, 1995-present
  • Franklin G. West Lifetime Achievement Award, Orange County Bar Association, 1995


  • Member: International Women's Forum/The Trusteeship, The Anti-Defamation League of Orange County and Long Beach's Regional Board
  • Past Member: The Orange County Performing Arts Center Board of Directors
  • Speaker for educational, legal, and business groups, as well as a contributing author on topics relating to law, business, and finance

Family Law

  • Service to Family Law Award, American Bar Association Family Law Section, 1993
  • Family Law Person of the Year, American Academy of Matrimonial Lawyers, 1993
  • Jurist of the Year, State Bar of California Family Law Section, 1991


  • Principal in Sonenshine Enterprises since 2004. In that capacity, she has invested in a number of women-led companies, and served as a trusted advisor to numerous female entrepreneurs
  • Co-Founder and Executive Managing Director, EquiCo (subsequently RSM EquiCo after being acquired by H&R Block in 2001), now known as McGladrey Capital Markets, 1999-2004
  • Associate Justice, California Court of Appeal, Fourth Appellate District, Division Three, 1982-1999
  • Judge, Orange County Superior Court, 1981-1982 (Presiding Judge, Family Law Panel)
  • Private law practice, Newport Beach, 1971-1981
  • J.D., Loyola School of Law, 1970 (St. Thomas More Honor Society)
  • B.A., Economics, University of California, Los Angeles, 1967

Counsel Comments

    • "Sheila Sonenshine is the absolute best settlement officer I have ever seen. She is knowledgeable and always fully prepared. Moreover she is practical and understands the goal of dispute resolution is to get all parties to believe they have made the best overall decision they can make, taking possible outcomes into account." 

      - Appellate Counsel
    • “Justice Sonenshine’s tenacity, business background, and common sense hands-on approach make her stand out among neutrals.” 

      - Legal strategist and former Sr. Vice President and General Counsel of one of the largest private real estate and development companies in the United States
    • "Justice Sonenshine has the experience, objectivity, and common sense to cut to the heart of an employment dispute and get the parties there with her."
    • "She put the lawyers, and the parties, in their place, and with tenacity, unmatched knowledge of the law and a presence that can only be described as breathtaking, gave us hope that we could actually settle a case where the parties could not have been further apart. Without her tireless assistance, exceptional mediation skills and unbridled commitment, there is no way this case could have settled."



Practice Areas

Available nationwide


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