MediaWiki:Apihelp-setglobalaccountstatus-param-statecheck/en

Optional MD5 of the expected current userid:username:hidden:locked. This is used to detect edit conflicts. The value of hidden must be an empty string if not hidden or the strings lists or suppressed. The value of locked must be 1 for locked, 0 for unlocked. Examples: 2128506:LeeSmith::0; 3839611:VandalGoblin:suppressed:1.