As part of LeastPrivilege.IdentityModel I wrote a claim set derived class that you can use to create your own custom claim sets. The DeferredLoadClaimSet lazily loads the claims (which potentially involves roundtrips to data stores) on demand when the claims are accessed for the first time.

You simply derive from DeferredLoadClaimSet and implement the LoadClaims method like this:

class CustomerClaimSet : DeferredLoadClaimSet
{
    string _customerName;

    public CustomerClaimSet(string customerName)
    {
        _customerName = customerName;
    }

    protected override void LoadClaims(out ClaimSet issuer, out IList<Claim> claims)
    {
        claims = CreateClaims();
        issuer = new ApplicationIssuerClaimSet(Constants.ApplicationIssuerName);
    }
}

The ApplicationIssuerClaimSet also derives from DeferredLoadClaimSet and can be used for custom issuers.

public class ApplicationIssuerClaimSet : DeferredLoadClaimSet
{
    string _issuerName = “Application Issuer”;

    public ApplicationIssuerClaimSet()
    { }

    public ApplicationIssuerClaimSet(string issuerName)
    {
        _issuerName = issuerName;
    }

    protected override void LoadClaims(out ClaimSet issuer, out IList<Claim> claims)
    {
        claims = new List<Claim>()
        {
            new Claim(ClaimTypes.System, _issuerName, Rights.Identity),
            new Claim(ClaimTypes.System, _issuerName, Rights.PossessProperty)
        };

        issuer = this;
    }
}

HTH