I know it sounds crazy, but is anyone here from the Netherlands and can read Dutch?
Here is the site to go to (I think):
http://autotelegraaf.nl/
Picked this up allegation from here (Feb):
http://forums.autoweek.com/thread.jspa?forumID=17&threadID=12968&tstart=0
AMSTERDAM - The legendary Volkswagen kever, icoon of the postwar German car industry, has not been developed by Ferdinand Porsche, but by Josef Ganz. That claims Paul Schilperoord in 'The Engineer' magazine.
It was simply nicked, according to the author. Already in 1928, Ganz used the name 'Volkswagen' for his concept car, which had a fixed chassis, engine in the back and rear-wheel drive.
He published in several German illustrated car magazines and registered some patents. According to Schilperoord, Ganz used already the name 'Maikäfer' [May beetle] for its prototype in 1931, long before that name became common practice for the new (postwar) Volkswagen.
A year after Adolf Hitler saw Ganz' Maikäfer in 1933 on a car exhibition, he announced plans for 'Deutsche Volkswagen' and handed Ferdinand Porsche the task to develop it. According to the writer of the article Porsche simply used the plans and designs of Josef Ganz. Ganz was of Jewish ancestors and thus unable to make a fist in nazi-Germany around that time. Already in 1933 he ran into problems and leaves for Switzerland.
Never recognition
The Porsche developed Volkswagen was ready in 1938, but went in production just after war. Eventually more than 21 million have been made when production was officially ceased in 2003. Josef Ganz never got recognition; for historians Porsche is the man behind the Volkswagen, thus Paul Schilperoord in 'The Engineer'.
[Source: AutoTelegraaf, Netherlands, quickly translated from dutch ]
PS: I don't know how old this rumor really is or if it's been disproved yet - just thought I would put better minds than mine to work on it.