2009 California Probate Code - Section 4695-4698 :: Article 3. Revocation Of Advance Directives

4695.  (a) A patient having capacity may revoke the designation of
an agent only by a signed writing or by personally informing the
supervising health care provider.
   (b) A patient having capacity may revoke all or part of an advance
health care directive, other than the designation of an agent, at
any time and in any manner that communicates an intent to revoke.

4696.  A health care provider, agent, conservator, or surrogate who
is informed of a revocation of an advance health care directive shall
promptly communicate the fact of the revocation to the supervising
health care provider and to any health care institution where the
patient is receiving care.

4697.  (a) If after executing a power of attorney for health care
the principal's marriage to the agent is dissolved or annulled, the
principal's designation of the former spouse as an agent to make
health care decisions for the principal is revoked.
   (b) If the agent's authority is revoked solely by subdivision (a),
it is revived by the principal's remarriage to the agent.

4698.  An advance health care directive that conflicts with an
earlier advance directive revokes the earlier advance directive to
the extent of the conflict.