Wis. Stat. § 409.605: Unknown debtor or secondary obligor.

A secured party does not owe a duty based on its status as secured party:

(1) To a person that is a debtor or obligor, unless the secured party knows:

(a) That the person is a debtor or obligor;

(b) The identity of the person; and

(c) How to communicate with the person; or

(2) To a secured party or lienholder that has filed a financing statement against a person, unless the secured party knows:

(a) That the person is a debtor; and

(b) The identity of the person.