Document Locator NumberSummary: This is an example of a document locator number.00 - File location code - Identifies the submission processing center where the form was filed.5 - Tax class - Identifies the type of tax.06 - Document code - Identifies the specific type of return or document within a tax class.106 - Julian Date - Denotes the numeric day of the year (January 7 is 007).XXX - Blocking series -Identifies the different categories of documents. Example: Block number 400 represents a full-paid (timely) document.00 - Serial number -Identifies the sequence of the forms within a block (00-99, with 00 being the first document).5 - Year digit - The last digit of the year in which the DLN was assigned.