Office national de la propriété industrielle
The Office national de la propriété industrielle (ONPI), was the French patent agency from 1902 to 1951. It succeeded the Office de Brevets of 1900-1902, and was followed by the current institution, the Institut national de la propriété industrielle (INPI).
For the history of the French patent offices including renamings and replacements, consult Institut national de la propriété industrielle on French Wikipedia.
Some of the antique publications cataloguing the years we are studying were published by the Office national de la propriété industrielle, as such. Newly found are a spectacular array of free ebooks, accessed via Google, designated under Frankreich Office National de la Propriété Industrielle, having been uploaded by the Bibliothek des Deutschen Museums.
This was found by way of Google Search frédéric malfait aviation, incidentally, and an analogous search using another inventor name may yield analogous results. In the case of this particular resource, antique data, typed during or shortly after our years of interest, and scanned much later, is searchable by way of our current data entry protocols.
These catalogues were compiled a posteriori, and follow variable protocols. A volume entitled "Brevet d'invention: Addition 1909, 10601 - 10800", for instance, will focus on certificates of addition, ordered as such, though the original parent patent number will be featured on each displayed original.
The singular "Brevet", "Brevet d'invention", may or may not reflect a typographical error on the part of the Bibliothek des Deutschen Museums. What is most key is that this "catalogue" is inclusive of complete patents, beyond the summary data found via the Bulletin Officiel de la propriété industrielle & commerciale and the Catalogue des Brevets d'Invention.