(a) The department:
(1) shall open each proposal received under this subchapter so as to avoid disclosure of contents to competing offerors during the process of negotiation; and
(2) may not disclose any information to an offeror that is derived from a proposal received from another offeror.
(b) After the award of a contract under this subchapter, each proposal submitted to the department is open for public inspection, except as provided by Chapter 552, Government Code.