(a) Filing office duties. For each record filed in a filing office, the filing office shall:

1. (1) assign a unique number to the filed record;
2. (2) create a record that bears the number assigned to the filed record and the date and time of filing;
3. (3) maintain the filed record for public inspection; and
4. (4) index the filed record in accordance with subsections (c), (d), and (e).

(b) File number. A file number must include a digit that:

1. (1) is mathematically derived from or related to the other digits of the file number; and
2. (2) aids the filing office in determining whether a number communicated as the file number includes a single-digit or transpositional error.

(c) Indexing: general. Except as otherwise provided in subsections (d) and (e), the filing office shall:

1. (1) index an initial financing statement according to the name of the debtor and index all filed records relating to the initial financing statement in a manner that associates with 1 another an initial financing statement and all filed records relating to the initial financing statement; and
2. (2) index a record that provides a name of a debtor which was not previously provided in the financing statement to which the record relates also according to the name that was not previously provided.

(d) Indexing: real-property-related financing statement. If a financing statement is filed as a fixture filing or covers as-extracted collateral or timber to be cut, the filing office shall index it:

1. (1) under the names of the debtor and of each owner of record shown on the financing statement as if they were the mortgagors under a mortgage of the real property described; and
2. (2) to the extent that the law of the commonwealth provides for indexing of records of mortgages under the name of the mortgagee, under the name of the secured party as if the secured party were the mortgagee thereunder, or, if indexing is by description, as if the financing statement were a record of a mortgage of the real property described.

(e) Indexing: real-property-related assignment. If a financing statement is filed as a fixture filing or covers as-extracted collateral or timber to be cut, the filing office shall index an assignment filed under Section 9–514(a) or an amendment filed under Section 9–514(b):

1. (1) under the name of the assignor as grantor; and
2. (2) to the extent that the law of the commonwealth provides for indexing a record of the assignment of a mortgage under the name of the assignee, under the name of the assignee.

(f) Retrieval and association capability. The filing office shall maintain a capability:

1. (1) to retrieve a record by the name of the debtor and:

   1. (A) if the filing office is described in Section 9–501(a)(1), by the book and page number assigned to the initial financing statement to which the record relates, in the case of unregistered land governed by chapter 36, and by the document number assigned to the initial financing statement to which the record relates, in the case of registered land governed by chapter 185; or
   2. (B) if the filing office is described in Section 9–501(a)(2), by the file number assigned to the initial financing statement to which the record relates; and
2. (2) to associate and retrieve with 1 another an initial financing statement and each filed record relating to the initial financing statement.