Patent classification systems
There have been many patent classification systems, varying over time, and varying between nations in the manner and the timing of their evolutions. To the present-day researcher, working at least largely online, and interested in finding antique patent material, international/global systems are of note in their retroactive projection of later international classifications onto antique, and national, patent material. Contemporary national patent websites, when they exist, vary in their overall quality and in terms of their active interfacing with the below-mentioned internation/global sytems and with the international websites through which we may gain at least a partial overview. All of this affects our manner of gathering data and in some instances it affects the manner in which we ultimately determine the antique patent classifications which were nationally applied.
International/global systems
- the CPC category system is the most modern and global, started 2010
- the IPC is the predecessor to the CPC, started 1971, per Wang (2018)]]
- IPC1-7 - an IPC version or variant
- sometimes there are specific references to the 2006 or other dates of one of these
National systems
- Australian patent classifications
- Austrian patent classifications
- Belgian patent classifications -- an evolving system which we can trace from it most raw and perhaps never completely standardized beginnings up through the two distinct and well-standardized stages which bring our data up through 1916
- British patent classifications
- Canadian patent classifications -- seems to look a lot like the USPC but the history of it is not known yet ; it was used till circa 1989
- Cuban patent classifications -- new to us, and thus far drawn from antique source material, possibly captured in an evolving state comparable to that of the furthest antique Belgian material, for instance ; thus far we've only seen indications of puerly phrasal-descriptive, rather than numerical or alphabetical, means of differentiating between types of patents.
- Danish patent classifications -- same as German so far as we know
- Dutch patent classifications -- an interesting case in which a late patent office founding led perhaps to an unusually modern-practical "early" national system, with no patchy evolution of aero-classification starting as a subclassification of marine, for instance, also interesting in that antique national classifications have been retroactively applied, in the manner of IPC and CPC, and somewhat in the interest of interfacing with these, most particularly as well the antique "Klasse 62" is retroactively and digitally used as a means of culling all the patent data found within that Klasse's "Groeps" ; the further-narrowed antique and national classification being sought is then determined by way of viewing the original, largely by way of Espacenet, after the patent or patents have been found.
- Finnish patent classifications -- same as German so far as we know
- French patent classifications -- dated in 50-year groups from 1858-1904 then from 1904-1958
- German patent classifications -- starting 1877-8, had the highest examination standards; until further notice this system was also used in Norway and Finland
- Hungarian patent classifications -- We have modern hearsay indicating that this system was "based on the German"; the "h" in HU V/h vaguely comports with this, though in the Hungarian case said "h" seems to zero down into the narrowest classification, “Osztály V/h”, containing all and only aero-material ; “Főosztály V” (which goes into railways and machinery more broadly) offers an instance in which a national aero-patent classification evolved from a pre-existing land-travel-based, rather than marine-based, broader classification.
- Italian patent classifications
- Luxembourgish patent classifications -- not yet established but we have examples
- Norwegian patent classifications
- Swedish patent classifications -- include examinations starting 1884; only US and DE were doing that already
- Swiss patent classifications
- US patent classification systems
Notes
In the scan of Patent FR-1903-325343 we have an instance of classifications by the German office written onto their copy of a French patent (albeit a member of an international family of which a German version probably also existed and required classification).
