For most extractions the limit is 30000 instruments (after file code and chain expansion).

Expansion is a mechanism by which some instrument identifiers will be expanded to many more. This is the case with chain RICs, as well as with ISINs, each of which may correspond to several RICs. So if you use ISINs, you must take into account that a single ISIN can expand to several RICs, and that the total number of RICs must not exceed the extraction limit.