51 Cal.3d 120, 793 P.2d 479, 271 Cal.Rptr. 146.
Prosser, pp. 188-191
Facts: The plaintiff went in for treatment of leukemia.† The defendant used cells from his spleen for profit.† The plaintiff sued for a bunch of stuff including conversion of his spleen cells, lack of informed consent, and breach of fiduciary duty.
Issue: Does a physician have a duty to inform the patient of his economic interest in a particular course of treatment?
Rule: A physician must tell the patient if he has personal interests that may affect his professional judgment.† If he fails to do so, he may be liable for malpractice based on breach of informed consent.
Analysis: The court uses three principles:
1. An adult has the right to control his own body.
2. Consent is only effective if it is informed consent.
3. The doctor must tell you about everything that is material to your decision to give consent.
Thus, a doctor, in getting your informed consent, must tell you about all of his interests that may affect his judgment, or else he may be liable for performing medical procedures without informed consent.
There is a competing interest in withholding information if giving the information would make a patient make a bad choice. †However, the court feels that this applies only in cases where the doctor is acting solely in the patientís best interests.† The court finds that this is not the case here.
Conclusion: A bunch of stuff happens, but essentially the court rules that there must be a consideration of the merits of the causes of action for lack of informed consent and breach of fiduciary duty on the part of the doctor who took the spleen.
 A duty of utmost good faith, trust, confidence, and candor owed by a fiduciary (such as a lawyer or corporate officer) to the beneficiary (such as a lawyer's client or a shareholder); a duty to act with the highest degree of honesty and loyalty toward another person and in the best interests of the other person (such as the duty that one partner owes to another).† Blackís 7th.