Keywords: missing, reconciliation
As we do every summer, institutions search for and clear books that are missing or overdue for more than 2 years (or 730 days). This process is explained in great detail in the following document:
This process allows libraries to clear from their holdings materials which are unlikely to be returned after two years. The Inter-Campus Services Committee (ICS) recommended to the Library Advisory Council (LAC) that no money exchange hands as a result of this process. This was recommended and approved because very few items (compared to the whole) became missing annually (less than 1% of the books requested) and the cost of issuing invoices and collecting monies far outweighed any monies collected.
So, the reconciliation process continues, but its only purpose is clear holdings of missing items. No invoices should be issued for payment from owning libraries. If the material remains 'missing', then the owning library clears the record from their holdings and life goes on.