A defective registration does not perfect a security interest. Certain defects only (broadly, defects which do not arise by error or omission of the secured party) are given a second chance with "grace periods", as explained below.
A defective registration that does not arise by error or omission of the secured party, but rather (for example) because the manufacturer or IP Australia subsequently changes a serial number, can validly perfect a security interest for a maximum of five (5) years (60 months), provided that the secured party does not know about
it1. Once the secured party has actual or constructive knowledge of the defect, the registration becomes invalid at the end of five (5) business days of the secured party having that knowledge, actual or constructive2.
The moral of the registration story is “search, register, search”, and double check (at the very least) that:
(a) the grantor’s details are correct; and
(b) any serial numbers for serial numbered property that must be registered against serial numbers (all consumer serial numbered property, and commercial aircraft) are correctly registered; and
(c) PMSIs are noted as PMSIs on the PPS Register.