Perfect, I have verified your reference. Thank you for sharing. It's confirmed now that CSIS clearance is valid for 4 years.Clearances
The applicant must not be subject to the prohibitions contained in sections 21 and 22 of the Act.
Applicant must pass all clearances: immigration, criminality (RCMP) and security (CSIS).
The CPC-S initiates all clearances. Validity for clearances is as indicated below.
https://www.canada.ca/en/immigration-refugees-citizenship/corporate/publications-manuals/operational-bulletins-manuals/canadian-citizenship/grant/adult.html
- Immigration: one year
- Criminality: one year
- Security: four years