Erlang vs Linux
Thu Feb 27 14:19:49 CET 2003
On Wed, 26 Feb 2003, Miguel Barreiro Paz wrote:
> Just out of curiosity, I've coincidentally found that patent
> EP0544637 (equivalent to WO9311484, for those out of the EU) effectively
> patents Erlang and OTP.
No it doesn't - The patent covers the combination of Erlang + A
particular application + A particular way of programming the
The language was Erlang as is was in 1993 which is very different to
today (this was before Funs, binaries, bit syntax, etc.) had been
added to the language so it refers to a *different* version of the
The particular application was a PABX programmed with the so called
"half call model"
The architecture was the so-called AOS (Application OS) this
was *before* BOS (basic OS) which was *before* OTP.
In no way can todays Erlang/OTP be considered as a minor variation
of the Erlang/AOS referred to in the patent - there are several major
an nonobvious additions since the work in 1993.
<aside> to be in violation of a patent you must violate *all* the
clauses of the patent - so for a Non PABX application you could
*never* be in violation of the patent </aside>
In any case even if the patent referred was applicable to the current
Erlang/OTP (which it is not) then 2.1b of the license would apply
2. Source Code License.
2.1. The Initial Developer Grant.
The Initial Developer hereby grants You a world-wide, royalty-free,
non-exclusive license, subject to third party intellectual property
(a) to use, reproduce, modify, display, perform, sublicense and
distribute the Original Code (or portions thereof) with or without
Modifications, or as part of a Larger Work; and
(b) under patents now or hereafter owned or controlled by Initial
Developer, to make, have made, use and sell (``Utilize'') the
Original Code (or portions thereof), but solely to the extent that
any such patent is reasonably necessary to enable You to Utilize
the Original Code (or portions thereof) and not to any greater
extent that may be necessary to Utilize further Modifications or
The initial developer was Ericsson. 2.1(b) says that you can
"Utilize" the system even if such utilisation is regulated by patents
"now or hereafter owned or controlled by Initial Developer".
Since Ericsson wants you to use Erlang (That's why it was released
as Open Source) - they explicitly granted you the right to use the
system - even if the use of the system was covered by their own
If a competitor to Ericsson (say Nortel) held such a patent then
their might have been a problem.
1) The patent refers to a historical vsn of Erlang + AOS + A PABX
application written in a particular manner. This is very different to
todays' Erlang + OTP.
2) Ericsson granted you the right to use OTP even when such use is
governed by patents held by Ericsson.
> I understand that its purpose is to guard
> Ericsson's shoulders, but the legal status of an opensourced system that
> is at the same time covered by a patent is a bit questionable without
> an explicit statement by the patent holder.
2.1(b) was an explicit statement
> Can anyone comment on this?
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