All proprietary information obtained by the commission or the secretary from any source, including all lists of grape rootstock nurseries, shall be confidential and shall not be disclosed except when required by a court order after a hearing in a judicial proceeding involving this chapter. Information on volume shipments, crop value, and any other related information required for reports to governmental agencies, financial reports to the commission, or aggregate sales and inventory information, and any other information that gives only totals, but excludes individual information, may be disclosed by the commission.