(1)    General rule: perfection by filing. Except as otherwise provided in sub. (2) and s. 409.312 (2), a financing statement must be filed to perfect all security interests and agricultural liens.

   (2)   Exceptions: filing not necessary. The filing of a financing statement is not necessary to perfect a security interest:

      (a)    That is perfected under s. 409.308 (4), (5), (6), or (7);

      (b)    That is perfected under s. 409.309 when it attaches;

      (c)    In property subject to a statute, regulation, or treaty described in s. 409.311 (1);

      (d)    In goods in possession of a bailee which is perfected under s. 409.312 (4) (a) or (b);

      (e)    In certificated securities, documents, goods, or instruments which is perfected without filing, control, or possession under s. 409.312 (5), (6), or (7);

      (f)    In collateral in the secured party’s possession under s. 409.313;

      (g)    In a certificated security which is perfected by delivery of the security certificate to the secured party under s. 409.313;

      (h)    In deposit accounts, electronic chattel paper, electronic documents, investment property, or letter-of-credit rights which is perfected by control under s. 409.314;

      (i)    In proceeds which is perfected under s. 409.315; or

      (j)    That is perfected under s. 409.316.

   (3)   Assignment of perfected security interest. If a secured party assigns a perfected security interest or agricultural lien, a filing under this chapter is not required to continue the perfected status of the security interest against creditors of and transferees from the original debtor.