This template notifies a user that he or she is suspected of using sockpuppets.
It is to be invoked on the user's talk page as: {{subst:socksuspectnotice|1=PUPPETMASTER}} replacing the term PUPPETMASTER with the account name of the suspected sockpuppeteer (without the "User:" prefix).
A case must have been created to report the sockpuppeteer (puppetmaster), otherwise the evidence link in this notification will be red, indicating that the page does not exist.
Complete directions for creating the case page, giving this notification, and posting warning boxes on the user pages of the suspected sockpuppets, are at Wikipedia:Sockpuppet investigations (WP:SPI).