Per Bowker, a Standard Address Number (SAN) is required when transmitting order data via any Book Industry Systems Advisory Committee EDI format.
The TitleLeaf EDI SAN setting (Admin > Management > Settings > Company) is used to store a company’s doesn’t have such functionality to transmit EDI files. Publishers commonly use third-party solutions. To facilitate the correlation of TitleLeaf’s ONIX product metadata transmissions with such third-party EDI order transmissions, TitleLeaf can store a publisher’s SAN identifier associated with their EDI solution.:
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If the EDI SAN is defined, TitleLeaf outputs the stored SAN it in the Header
composite of ONIX 2 and ONIX 3 packages to facilitate correlation to EDI data by third parties :
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In this way, recipients of TitleLeaf’s ONIX files (eg, Follett) .
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can link the product metadata contained therein to the EDI order data received separately.
Reference: