<PackageReference Include="BouncyCastle.Cryptography" Version="2.7.0" />

Org.BouncyCastle.Bcpg.Sig.SignerUserId

Signature Subpacket containing the User ID of the identity as which the issuer created the signature.
namespace Org.BouncyCastle.Bcpg.Sig { public class SignerUserId : SignatureSubpacket { public SignerUserId(bool critical, bool isLongLength, byte[] data); public SignerUserId(bool critical, string userId); public string GetId(); public byte[] GetRawId(); } }