(1)    Notification date. In this section, “notification date” means the earlier of the date on which:

      (a)    A secured party sends to the debtor and any secondary obligor an authenticated notification of disposition; or

      (b)    The debtor and any secondary obligor waive the right to notification.

   (2)   Notification of disposition required. Except as otherwise provided in sub. (4), a secured party that disposes of collateral under s. 409.610 shall send to the persons specified in sub. (3) a reasonable, authenticated notification of disposition.

   (3)   Persons to be notified. To comply with sub. (2), the secured party shall send an authenticated notification of disposition to:

      (a)    The debtor;

      (b)    Any secondary obligor; and

      (c)    If the collateral is other than consumer goods:

         1.    Any other person from which the secured party has received, before the notification date, an authenticated notification of a claim of an interest in the collateral;

         2.    Any other secured party or lienholder that, 10 days before the notification date, held a security interest in or other lien on the collateral perfected by the filing of a financing statement that:

            a.    Identified the collateral;

            b.    Was indexed under the debtor’s name as of that date; and

            c.    Was filed in the office in which to file a financing statement against the debtor covering the collateral as of that date; and

         3.    Any other secured party that, 10 days before the notification date, held a security interest in the collateral perfected by compliance with a statute, regulation, or treaty described in s. 409.311 (1).

   (4)   Subsection (2) inapplicable: perishable collateral; recognized market. Subsection (2) does not apply if the collateral is perishable or threatens to decline speedily in value or is of a type customarily sold on a recognized market.

   (5)   Compliance with sub. (3) (c) 2. A secured party complies with the requirement for notification prescribed by sub. (3) (c) 2. if:

      (a)    Not later than 20 days or earlier than 30 days before the notification date, the secured party requests, in a commercially reasonable manner, information concerning financing statements indexed under the debtor’s name in the office indicated in sub. (3) (c) 2.; and

      (b)    Before the notification date, the secured party:

         1.    Did not receive a response to the request for information; or

         2.    Received a response to the request for information and sent an authenticated notification of disposition to each secured party or other lienholder named in that response whose financing statement covered the collateral.