California Code, Revenue and Taxation Code - RTC § 18763

(a) An individual may designate on the tax return that a contribution in excess of the tax liability, if any, be made to the California Alzheimer's Disease and Related Dementia Research Voluntary Tax Contribution Fund, that is established by Section 18764.

(b) The contributions shall be in full dollar amounts and may be made individually by each signatory on the joint return.

(c) A designation under subdivision (a) shall be made for any taxable year on the individual return for that taxable year, and once made shall be irrevocable. In the event that payments and credits reported on the return, together with any other credits associated with the individual's account, do not exceed the individual's tax liability, the return shall be treated as though no designation has been made.

(d) The Franchise Tax Board shall revise the forms of the return to include a space labeled the “Alzheimer's Disease and Related Dementia Voluntary Tax Contribution Fund” to allow for the designation permitted under subdivision (a). The forms shall also include in the instructions information that the contribution may be in the amount of one dollar ($1) or more and that the contribution shall be used to conduct research relating to the cure and treatment of Alzheimer's disease.

(e) A deduction shall be allowed under Article 6 (commencing with Section 17201) of Chapter 3 of Part 10 for any contribution made pursuant to subdivision (a).