IFC - Industry Foundation Classes/IFC concepts/IFC cost concepts
From Wiki.OSArch
A cost schedule can exist
A cost schedule is a collection of cost items, used for a specified purpose. Typical purposes are cost plans and tenders.
Note: there is no explicit documentation which explains how a cost schedule is related back to the project or context. Therefore, in the absence of documentation, we are assuming that we declare it to the project as shown. However, this is only an assumption.
Source: None