IDEA License

[Ulrich Mueller]

>>>>> On Tue, 26 Mar 2013, Julian H Stacey wrote:

> OK I added Ulrich M to cc
> He can add URL to wikipedia of expiry date of Japan IDEA paent
> if he wants, or I will if he mails it me.
> A dead patent is a good patent ;-)

IANAL, TINLA, but the term of patent in Japan seems to be 20 years and
it was filed in 1991. Concerning the exact date, here's what I had
written in my message to the FSF, about one year ago:

| To the best of my knowledge, the IDEA algorithm was covered by the
| following patents held by Ascom Tech AG, Bern, Switzerland:
|  - Europe: EP0482154 [1]
|  - U.S.:   5,214,703 [2]
|  - Japan:  JP3225440
| These patents were filed in 1991. All sources (see [3] and [4] and
| references cited therein) seem to agree that the European and the
| Japanese patent both have expired on 2011-05-16.
|
| About the U.S. patent the situation seems not so clear, as there are
| several expiry dates mentioned. The PGP FAQ [3] says it has expired on
| 2010-05-25 whereas Wikipedia [4,5] mentions 2011-05-16 and 2012-01-07.
| However, none of these dates is later than 2012-01-07. So I think it
| is safe to assume that the U.S. patent has expired, too.
|
| [1] <http://register.epoline.org/espacenet/application?number=EP91908542>
| [2] <http://www.google.com/patents?vid=5214703>
| [3] <http://www.pgp.net/pgpnet/pgp-faq/#PATENT-IDEA>
| [4] <http://en.wikipedia.org/wiki/International_Data_Encryption_Algorithm>
| [5] <http://en.wikipedia.org/wiki/Talk:International_Data_Encryption_Algorithm#Explanation_of_U.S._patent_expiration>

Ulrich