The following creditors are deemed equal to those specified under section 50:
1. creditors to whom the debtor has assigned a movable item or a right in order to secure a claim;
2. creditors with a right to withhold an object in consideration of their improvement of the object as far as their claim from such improvement does not exceed the still existing improvement;
3. creditors with a right to withhold an object under the provisions of the Commercial Code;
4. the Federation, the Länder, municipalities and municipal associations with regard to objects subject to custom duties and tax under legal provisions to secure the payment of public dues.