[DB-SIG] Standardized Date-Time class

[Magnus Lycka]

At 12:16 1997-12-11 -0500, Jeffrey C. Jacobs wrote:
>	I will say that on the specific case of the Reingold-Dershowitz 
>Calendrical algorithms, I am now "dirty", having seen the Lisp source of the 
>code they are *indending* to patent.  Thus, I am pretty forbidden from
writing 
>any Calendar converter and distributing it directly, even if under the GNU 
>license.  As Magnus has implied, having a binary distribution is different
than 
>having the source, however, it is not perfect.

If they GET a patent, their patented invention is theirs. Clean room
procedures
doesn't matter then. A patent gives you exclusive rights to an invention, 
whether someone else also invents it completely independendly does not matter.

I don't think you can patent source code though, any more than you can patent
blue prints. As far as I understand the patent must refer to an invention.
For instance the algorithms for calculating these calendars can be considered
inventions, but since they have been used for hundreds of years it might be
tricky to patent them... I'm no patent lawyer as I said, but it's really a
bit weird if patents are allowed that are just a matter of making some well
know and used system structured. As I haven't seen their algorithms I don't
really know what I'm talking about here. I must assume that it really is an
invention of some sort.

I guess you can write any calendar converter you like as long as you don't
use their algorithm, as long as you haven't made some kind of agreement 
regarding this. 

>	One example you can take from a book I once read about the development of 
>a microchip which is supposed to emulate some other, rival company chip.
The 
>way the company avoids copyright and patent infringement is by having an 
>independent entity fully analyze and document the cause and effect of every 
>possible input on the chip, and then without letting the analyzers contact
in 
>any way the engineers, the engineers proceed to build a chip which exactly 
>follows the specification defined by the chip researchers, who themselves
have 
>become "dirty" as they have seen the original chip.  Thus in that way, the
new 
>chip engineers will have never seen the rival chip, and thus be "clean"
from any 
>potential lawsuit.

Copyright: yes, patent: perhaps not. If they just 'happen' to come up with the
same solution as the chip they copied from, it's still a patent infringement.
It is AFAIK perfectly legal to analyze the current patents when you develop
something similar to a patented product. In fact, you ought to do this to make
sure you don't violate some patent. Patent searches is stantard procedure in
large companies as I understand it. Actually, some (japanese) companies are
very good at analyzing patents to see how you can apply for patents that are
related to an interesting patent from a competitor. For instance if you have
the patent on boiling eggs, I make all sorts of patents on using boiled eggs,
and then your patent is worthless unless you buy licences for my patents. :-)

>	Just stepping back to the original point of developing a set Calendar
>converters for Python, the code as I understand it that Christian Egli
ported 
>from Reingold-Dershowitz is considered in the public domain, as the
authors are 
>not trying to maintain any hold on the people using it.  It is only for
the more 

Copyrights apply by default. Formally it might even be considered a copyright 
violation that I quote you right now. In this particular case I think I could 
claim that it's obvious that you permit people in this discussion group to
quote 
you in their replies, but that code is made available does NOT put it in the 
public domain. It gets into the public domain when the copyright lapses due
to 
old age. (75 years after authors death?) You are on thin ice as soon as you
use 
code written by someone else unless you have an agreement that you might use 
it, such as a BSD, GPL etc licence. I haven't read the copyright notice on 
these programs, but if nothing is said about public use, it's not in the
publlic
domain. (Formally at least.) On the other hand (this might well vary from
country 
to country) I think there are general legal rules saying that if you are
aware 
that something happens and don't do anything about it for a long time you
have 
basically agreed to it and loose your claims.

>In conclusion, all I suggest is that any Calendar converters we include in 
>Python be modular and inter-changeable, so that people using Python
commercially 
>can use those in public domain, but need not use the copyrighted ones, and 
>people wishing to do Calendrical research can request the full Calendar
library 
>set, and simply plug it into python as if they were part of the standard 
>distribution.  Simply, have Gregorian.pyc, Julian.pyc, Hebrew.pyc,
Islam.pyc and 
>ISODate.pyc be part of the standard distribution, and optionally one can add 
>Hindu1.pyc, Hindu2.pyc, French.pyc, and Chinese.pyc to their installation
and 
>import them as they do the standard Calendar libraries.

Agreed.

I'll shut up about patents and copyrights now. Sorry to deviate, but
(unfortunately) it's something that we all need to be aware of...


	Magnus

--
Magnus Lycka, S/W Engineer, M.Sc.E.E; Folktrov. 6C, 907 51 Umea, Sweden
Tel: +46(0)90 198 498, GSM: +46(0)70 582 80 65, Fax: +46(0)70 612 80 65
<mailto:magnus.lycka@tripnet.se>         <http://www1.tripnet.se/~mly/>


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