Section 6381 Of Article 2. Exemptions From Sales Tax From California Revenue And Taxation Code >> Division 2. >> Part 1. >> Chapter 4. >> Article 2.

. There are exempted from the computation of the amount of the sales tax the gross receipts from the sale of any tangible personal property to:
  (a) The United States, its unincorporated agencies and instrumentalities;
  (b) Any incorporated agency or instrumentality of the United States wholly owned by the United States or by a corporation wholly owned by the United States;
  (c) The American National Red Cross, its chapters and branches.