https://learn.microsoft.com/en-us/dotnet/api/system.security.policy.gacinstalled?view=netframework-4.8.1&redirectedfrom=MSDN
GacInstalled Class (System.Security.Policy) | Microsoft Learn
Confirms that a code assembly originates in the global assembly cache (GAC) as evidence for policy evaluation. This class cannot be inherited.
system security policyclassmicrosoftlearn