Property I, Pages 56–68

Moore v. Regents of the University of California

Supreme Court of California, 1990


Moore had cancer and went to Dr. Golde of the UCLA medical center for treatment. Golde recommended a splenectomy, which Moore then underwent. While there, Golde noticed that Moore's T-lymphocytes, a certain type of white blood cell, overproduced certain lymphokines, proteins that regulate the immune system. After Moore's surgery and three years of research, Golde and another researcher named Quan used Moore's abnormal T-lymphocytes to developed a cell line that could produce lots of lymphokines. The Board of Regents of the University applied for a patent on the Mo cell line, as it was now known, listing Golde and Quan as the inventors. Gold later negotiated with a private company called Genetics Institute to give them exclusive rights to the research materials and any product in exchange for Golde receiving 75,000 shares of the Genetics common stock and Gold and the Regents receiving $110,000 per year for three years. Once Moore discovered the nature, extant, and results of the research, Moore sued Golde, Quan, the Regents, Genetics, and others.

Procedural History:

The defendants filed a general demurrer to the complainant and the trial court sustained it. The court of appeal reversed, concluding that Moore's complaint stated a cause of action for conversion.


Does using someone's cells for medical purposes without authorization constitute a conversion?

Plaintiff's Argument:

The defendants had converted his T-lymphocytes by using them without his consent in their research to produce the Mo cell line. By failing to inform Moore of the planned use of his cells, Golde had not gotten his consent to perform the splenectomy and therefore breached his duty as Moore's physician.

Defendant's Argument:

Golde tried to explain his research to Moore before the surgery. At the time, Golde tried to create cell lines from all his patients, to which Moore orally consented.


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To establish a conversion, plaintiff must establish an actual interference with his ownership or right of possession. . . . Where plaintiff neither has title to the property alleged to have been converted, nor possession thereof, he cannot maintain an action for conversion.


  • Since Moore did not expect to retain possession of his cells after the surgery, he must have retained an ownership interest in them for there to be conversion. However, there is evidence against this:

    1. No judicial decision supports Moore's decision.
    2. California statute drastically limits continuing interest in removed cells.
    3. The products derived from these cells cannot possibly be Moore's because they are factually and legally distinct because they were grown by human ingenuity—they were not merely a simple byproduct of Moore's spleen. Given this, a conversion was not present under current rules.
  • It would also be inappropriate to extend conversion to encompass this:

    1. A fair balancing of relevant policy considerations counsels against extending the tort.
    2. The problems in this area are better suited to legislative resolution.
    3. The tort of conversion is not necessary to protect patients' rights.
  • Extending it would also be unwise in regards to policy because:

    1. A competent patient had a right to make autonomous medical decisions.
    2. Innocent parties who are engaged in socially useful activities, like researchers who believe they are acting in harmony with their patients' wishes, should not be threatened with disabling civil liability.


No, using someone's cells for medical purposes without authorization does not constitute a conversion. Moore's complaint had a cause of action for lack of informed consent and breach of fiduciary duty, but nor for conversion, for which the suit was dismissed.


A conversion is a tort of an unlawful taking of someone else's property.