The numerical collection of the Netherlands Industrial Property Office (BIE) includes the national patent documents belonging to the PCT minimum documentation as specified in Rule 34.1(b)(i) and (c) PCT (see also IX, 2.1), but also includes patent documents of a number of countries not belonging to the PCT minimum documentation. For some countries, it also includes patent documents or abstracts published before 1920. A complete updated list ("Maandelijks Overzicht Octrooipublicaties") is published every month and is available in the library of the BIE.

The collection furthermore includes the gazettes of all the countries present in the list, in some instances going back even further than the patent collections themselves.