Proprietary Information (PROPIN) definition in Computer Security terms:
Definition(s): Material and information relating to or associated with a company’s products, business, or activities, including but not limited to financial information; data or statements; trade secrets; product research and development; existing and future product designs and performance specifications; marketing plans or techniques; schematics; client lists; computer programs; processes; and know- how that has been clearly identified and properly marked by the company as proprietary information, trade secrets, or company confidential information. The information must have been developed by the company and not be available to the Government or to the public without restriction from another source.
Source(s): CNSSI 4009-2015
reference: CSRC Glossary