Table of patent sources by country

The table lists the countries with the most patents in our database, and the most significant sources. (The counts include some patents that are not related to aeronautics, or are out of our period of interest.) There will be many more from some of these countries. Google patents has information for most of these, generally those which are available on espacenet too. For the oldest patents we usually don’t have complete information, e.g. not the author’s full name. From several countries the search is challenging as the inventors names are not recorded, or not recorded in a standard way.

Country (Abbreviation)	Patents here	Notes on the country's early aero patent data
France (FR)	5036	Digitized and available on espacenet back to about 1900. There are a variety of earlier sources with summaries or lists: Online INPI.fr historic patent database, searchable from http://bases-brevets19e.inpi.fr/index.asp?page=rechercheAvancee; patents were indexes in the Catalogue des brevets d'invention and Bulletin Officiel de la Propriété Industrielle in the 1880s; and in USPTO’s Subject-Matter Index of Patents for Invention, France (1883); L'Aérophile issues 1898-1905 listed aero patents specifically; Aéro-Manuel, 1914, lists some aero patents
United States (US)	4790	All granted patents have been digitized and are available both on the USPTO site and on espacenet. The original national classifications of each patent are not easily available.
Great Britain (GB)	3724	Digitized and generally available on espacenet back to about 1905. Technical classifications used at the time are not easily available. Summaries of aero patents appeared in Brewer and Alexander's 1893 book, in Neilson (1910), and in many issues of Aeronautical Journal. The Abridgements of Patent Specifications listed others and some information about classification.
Germany (DE)	882	Patents began 1877; All German patents have data available at DMPA; most are digitized and online at espacenet, DPMA, or Otto-Lilienthal Museum. Regular lists of aero patents appeared in Jahrbuch über die Fortschritte auf allen Gebieten der Luftschiffahrt and Deutsche Zeitschrift für Luftschiffahrt. Alexander-Katz (1912) lists some. We exclude Gebrauchsmuster patents (quick patents) from this study for now.
Hungary (HU)	327	Hungary's patent office was distinct from Austria's. All historic patents are on the current Hungarian patent office web site, not espacenet.
Austria (AT)	153	Had a patent office distinct from Hungary's. Patents are on espacenet and are all indexed by DPMA.
Belgium (BE)	148	Patents from the early aero period are not on espacenet; catalogs with summary information are in Recueil des Brevets d'Invention volumes, available in USPTO library; Originals available at archives in Brussels. Very antique and very raw indexed patent data may be found via the digitized material provided by the State Archives of Belgium.
Italy (IT)	90	We haven't found the patent documents online but summaries are listed in the regular government gazette Bollettino della proprietà intellettuale
Canada (CA)	78	Granted patent documents from aero era are digitized and available from CIPO or espacenet
Switzerland (CH)	70	All patents have some data at DPMA, and documents are available at espacenet
Spain (ES)	66	Most are indexed at espacenet but documents are not often available.
Norway (NO)	49	Many patents from early aero era are not on espacenet ; Short descriptions available were library in Trondheim
New Zealand (NZ)	27	Patents from early aero era are available on IPONZ web site; not on espacenet we think.
Denmark (DK)	21	Patents start about 1864. They are on espacenet.
India (IN)	16	Had a patent office distinct from Great Britain's; Patents are on espacenet
Australia (AU)	16	Australia's early aero patents are all available from the Australian Patent Office web site; we think they are not generally on espacenet