BSD and MIT license "compliance" with the MS-PL

Matthew Flaschen matthew.flaschen at
Fri Apr 17 21:27:47 UTC 2009

Tzeng, Nigel H. wrote:
> It says you have to tell folks where to find the code.  There's no
> obligation for you to distribute the source with the binary as you
> assert.  The notice fulfills my obligations to MPL.

Okay, if you thought I meant, /You have to put the source on the same
physical distribution medium as the binary/ I apologize for not being
clear.  When distributing, it is sufficient to provide notice of the
source location.

> Mozilla is not misinterpreting it's license wrong because the FAQ
> clearly indicates that your obligations in distributing binary from
> unmodified source is to add a conspicuous notice stating where to
> find the original source.

The FAQ says, "You must add a conspicuous notice stating where to find
the exact source to the binary you are distributing [3.6] "

Note the reference to 3.6.  3.6 has only one reference to notifying
recipients of source availability:

"You may distribute Covered Code in Executable form only if the
requirements of Sections 3.1, 3.2, 3.3, 3.4 and 3.5 have been met for
that Covered Code, and if You include a notice stating that the Source
Code version of the Covered Code is available under the terms of this
License, including a description of how and where You have fulfilled the
obligations of Section 3.2. The notice must be conspicuously included in
any notice in an Executable version, related documentation or collateral
in which You describe recipients' rights relating to the Covered Code."

Note that both clauses incorporate 3.2.

> You are also not obligated to host the source for the 12 months as
> stipulated in 3.2 for modified source.

Are you saying the source can disappear before 12 months?  The MPL
explicitly says, "You are responsible for ensuring that the Source Code
version remains available even if the Electronic Distribution Mechanism
is maintained by a third party."

> Heck, you can even not supply the entire modified source and just the
> diffs and point upstream for the unmodified source according to their
> FAQ.

That is probably fine, as long as you ensure that it will remain for 12
months (per above quote).  If the Mozilla source disappeared before 12
months, you would be liable.

> You can claim that MPL isn't copyleft but I think the burden is on
> you to provide evidence to the contrary.

I am claiming it /is/ copyleft.  I said /hypothetically if/ it didn't
require that users could get source (but it does require this) it
wouldn't be copyleft.

>> Where is it categorized as copyleft (besides the FSF list)?
> many lists are there?

I'm not saying a official list.  The source could be anything: Lawrence
Lessig, SFLC, Microsoft, Debian, whatever.

But the real question is, "What is your definition of copyleft?" and who
supports it.

Matt Flaschen

More information about the License-discuss mailing list