Section 705(a) of the California Corporations Code provides that no proxy is valid after the expiration of 11 months from the date thereof unless otherwise provided in the proxy.  This is a reflection of the fact that proxies are typically obtained in connection with annual meetings.  If a longer term proxy is desired, then the proxy must so provide.  Even a valid proxy's life may be cut short by revocation.  Section 705(b) specifies how a a proxy may be revoked and Section 705(e) specifies when a proxy may be irrevocable.  

If the corporation is a nonprofit corporation, an additional rule applies.  Sections 5613(b), 7613(b), and 9417(b) each provides that no proxy “shall be valid after the expiration of 11 months from the date thereof unless otherwise provided in the proxy, except that the maximum term of any proxy shall be three years from the date of execution.”

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