(a) A business or other person shall not reidentify, or attempt to reidentify, information that has met the requirements of paragraph (4) of subdivision (a) of Section 1798.146, except for one or more of the following purposes:

1. (1) Treatment, payment, or health care operations conducted by a covered entity or business associate acting on behalf of, and at the written direction of, the covered entity. For purposes of this paragraph, “treatment,” “payment,” “health care operations,” “covered entity,” and “business associate” have the same meaning as defined in Section 164.501 of Title 45 of the Code of Federal Regulations.
2. (2) Public health activities or purposes as described in Section 164.512 of Title 45 of the Code of Federal Regulations.
3. (3) Research, as defined in Section 164.501 of Title 45 of the Code of Federal Regulations, that is conducted in accordance with Part 46 of Title 45 of the Code of Federal Regulations, the Federal Policy for the Protection of Human Subjects, also known as the Common Rule.
4. (4) Pursuant to a contract where the lawful holder of the deidentified information that met the requirements of paragraph (4) of subdivision (a) of Section 1798.146 expressly engages a person or entity to attempt to reidentify the deidentified information in order to conduct testing, analysis, or validation of deidentification, or related statistical techniques, if the contract bans any other use or disclosure of the reidentified information and requires the return or destruction of the information that was reidentified upon completion of the contract.
5. (5) If otherwise required by law.

(c) Beginning January 1, 2021, any contract for the sale or license of deidentified information that has met the requirements of paragraph (4) of subdivision (a) of Section 1798.146, where one of the parties is a person residing or doing business in the state, shall include the following, or substantially similar, provisions:

1. (1) A statement that the deidentified information being sold or licensed includes deidentified patient information.
2. (2) A statement that reidentification, and attempted reidentification, of the deidentified information by the purchaser or licensee of the information is prohibited pursuant to this section.
3. (3) A requirement that, unless otherwise required by law, the purchaser or licensee of the deidentified information may not further disclose the deidentified information to any third party unless the third party is contractually bound by the same or stricter restrictions and conditions.