There are a few different possibilities:
- In order for holdings to display accurately in WorldCat.org, a library must have one of the visibility subscription options here: Web visibility program
- Due to the format/edition grouping feature, an item's detail page will not necessarily show the edition on which your library has a holding. To show holdings for all editions of the same resource, toggle the link at the top right of the list that will read either "just this edition" or "any edition."
- If neither of these are true for your library or your library has questions, please contact OCLC Support.
Visit Web visibility program to request a quote for these services.