US patent No. 3,941,932 (relating broadly to electroacoustics) refers in its
disclosure to "German patent specification 967,167" which is supposed to
relate to the same subject matter. My client obtained a copy of the German
patent (Patentschrift No. 967,167, granted October 17, 1957). The only
problem is that this patent is directed to pneumatic brakes, not to
electroacoustics.
I am aware of the fact that the German patent system distinguishes between a
patent (Patentschrift) and a published patent application
(Offenlegungsschrift), as do patent systems of many countries. In some
countries patents and published applications are numbered as two (or
sometimes more) independent series, so that the number is not always
sufficient to identify unambiguously a document, i.e., one needs both the
number _and_ the kind of document. I suspected that the document referred
to in US 3,941,932 may have been an Offenlegungsschrift with the same
number, distinct from the Patentschrift 967,167. Was my suspicion correct?
Do German patents retain the number under which they were published (as is
the case in Canada)? What was the numbering system in place in 50s and has
it changed since then? My client tried to order Offenlegungsschrift 967,167
(as opposed to Patentschrift 967,167), but was told that "there is only one
kind of document DE 967,167".
Assuming that I am wrong, meaning that the Patentschrift retains upon grant
the same number as the corresponding Offenlegungsschrift, the only possible
explanation is that the German patent number cited in the US patent is
incorrect. I do have a presumed name of the inventor of the German
patent/patent application. Is there any database of German patents going
back to 50s which could be searched to check if there are any patents
showing this inventor name?
Any hints and suggestions would be greatly appreciated.
Kazimierz T. Kaminski, Ph.D.
Patent Agent
InfoSciTech Information Consultants Inc.
ktk@infoscitech.ca
http://www.infoscitech.ca