John Moore was treated for hairy-cell leukemia at the University of California, Los Angeles Medical Center by Dr. David Golde. During treatment, Moore’s spleen and other bodily materials were removed, and Golde and other defendants allegedly knew those cells had unique commercial and research value. Without informing Moore, the defendants developed a valuable cell line from his cells, obtained a patent, and entered commercial arrangements related to the research. Moore sued, alleging, among other claims, conversion and breach of fiduciary duty based on the undisclosed use of his cells.
Does a patient retain a property interest in excised cells sufficient to support a conversion claim when physicians use those cells for research and commercial development without the patient’s knowledge or consent?
A patient whose cells have been removed in the course of medical treatment does not retain an ownership interest in those excised cells sufficient to support an action for conversion. However, a physician has fiduciary and disclosure obligations to reveal personal interests unrelated to the patient’s health that may affect medical judgment, and failure to do so can support claims for breach of fiduciary duty and lack of informed consent.
The court held that Moore could not state a cause of action for conversion because California law did not recognize his continuing property interest in excised cells. The court allowed his claims for breach of fiduciary duty and lack of informed consent to proceed based on the physicians’ alleged failure to disclose research and economic interests.
The court reasoned that extending conversion liability to excised human tissues would conflict with existing statutory limits on the use and disposition of human biological materials and could hinder socially valuable medical research. It also emphasized that the patented cell line was legally and factually distinct from Moore’s original cells, undermining the claim that defendants had simply appropriated his property. At the same time, the court concluded that physicians must disclose conflicts of interest and research or economic motives that could affect treatment decisions because patients are entitled to make informed choices about their medical care. Those disclosure-based duties adequately addressed the alleged wrong without creating a broad new property right in human tissues.
Justice Mosk, joined in part by Justice Kennard, argued that Moore should be able to pursue a conversion claim because denying a property remedy allowed others to profit from his body without consent. The dissent viewed the majority’s refusal to recognize Moore’s interest as inconsistent with basic principles protecting individuals against unauthorized appropriation.
Moore is the leading case rejecting patient property rights in excised tissues while recognizing that doctors must disclose research and financial interests affecting treatment. It sharply separates property-based claims from informed-consent and fiduciary-duty claims in biomedical research disputes. The case is frequently discussed alongside informed-consent precedent such as Cobbs v. Grant, 8 Cal. 3d 229 (1972), and in debates over commercialization of human biological materials and patient autonomy.
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