<s>
License	B-License
proliferation	I-License
is	O
the	O
phenomenon	O
of	O
an	O
abundance	O
of	O
already	O
existing	O
and	O
the	O
continued	O
creation	O
of	O
new	O
software	B-License
licenses	I-License
for	O
software	O
and	O
software	B-Application
packages	I-Application
in	O
the	O
FOSS	B-License
ecosystem	O
.	O
</s>
<s>
License	B-License
proliferation	I-License
affects	O
the	O
whole	O
FOSS	B-License
ecosystem	O
negatively	O
by	O
the	O
burden	O
of	O
increasingly	O
complex	O
license	O
selection	O
,	O
license	O
interaction	O
,	O
and	O
license	O
compatibility	O
considerations	O
.	O
</s>
<s>
As	O
the	O
number	O
of	O
licenses	O
increases	O
,	O
the	O
probability	O
that	O
a	O
free	B-License
and	I-License
open-source	I-License
software	I-License
(	O
FOSS	B-License
)	O
developer	O
will	O
want	O
to	O
merge	O
software	O
that	O
are	O
available	O
under	O
incompatible	O
licenses	O
increases	O
.	O
</s>
<s>
There	O
is	O
also	O
a	O
greater	O
cost	O
to	O
companies	O
that	O
wish	O
to	O
evaluate	O
every	O
FOSS	B-License
license	O
for	O
software	B-Application
packages	I-Application
that	O
they	O
use	O
.	O
</s>
<s>
Strictly	O
speaking	O
,	O
no	O
one	O
is	O
in	O
favor	O
of	O
license	B-License
proliferation	I-License
.	O
</s>
<s>
License	B-License
proliferation	I-License
is	O
especially	O
a	O
problem	O
when	O
licenses	O
have	O
only	O
limited	O
or	O
complicated	O
license	O
compatibility	O
relationships	O
with	O
other	O
licenses	O
.	O
</s>
<s>
Therefore	O
,	O
some	O
consider	O
compatibility	O
with	O
the	O
widely	O
used	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
(	O
GPL	B-License
)	O
an	O
important	O
characteristic	O
,	O
for	O
instance	O
David	O
A	O
.	O
Wheeler	O
as	O
also	O
the	B-Operating_System
Free	I-Operating_System
Software	I-Operating_System
Foundation	I-Operating_System
(	O
FSF	O
)	O
,	O
who	O
maintains	O
a	O
list	O
of	O
the	O
licenses	O
that	O
are	O
compatible	O
with	O
the	O
GPL	B-License
.	O
</s>
<s>
On	O
the	O
other	O
hand	O
,	O
some	O
recommend	O
Permissive	B-License
licenses	I-License
,	O
instead	O
of	O
copyleft	B-License
licenses	I-License
,	O
due	O
to	O
the	O
better	O
compatibility	O
with	O
more	O
licenses.xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx1	O
{{cite	O
web	O
|url	O
=	O
|work	O
=	O
Open-Source	O
Software	O
-	O
Develop	O
,	O
share	O
,	O
and	O
reuse	O
open	O
source	O
software	O
for	O
public	O
administrations	O
|title	O
=	O
Licence	O
Compatibility	O
and	O
Interoperability	O
|publisher	O
=	O
joinup.ec.europa.eu	O
|quote	O
=	O
The	O
licences	O
for	O
distributing	O
free	O
or	O
open	O
source	O
software	O
(	O
FOSS	B-License
)	O
are	O
divided	O
in	O
two	O
families	O
:	O
permissive	O
and	O
copyleft	B-License
.	O
</s>
<s>
Permissive	B-License
licences	I-License
(	O
BSD	O
,	O
MIT	O
,	O
X11	O
,	O
Apache	O
,	O
Zope	O
)	O
are	O
generally	O
compatible	O
and	O
interoperable	O
with	O
most	O
other	O
licences	O
,	O
tolerating	O
to	O
merge	O
,	O
combine	O
or	O
improve	O
the	O
covered	O
code	O
and	O
to	O
re-distribute	O
it	O
under	O
many	O
licences	O
(	O
including	O
non-free	O
or	O
“	O
proprietary	O
”	O
)	O
.	O
</s>
<s>
|	O
access-date	O
=	O
2015-05-30	O
|	O
url-status	O
=	O
dead	O
|	O
archive-url	O
=	O
https://web.archive.org/web/20150617130550/https://joinup.ec.europa.eu/software/page/licence_compatibility_and_interoperability	O
|	O
archive-date	O
=	O
2015-06-17	O
}}	O
</ref>	O
The	O
Apache	O
Foundation	O
for	O
instance	O
criticizes	O
the	O
fact	O
that	O
while	O
the	O
Apache	B-Application
License	I-Application
is	O
compatible	O
with	O
the	O
copyleft	B-License
GPLv3	O
,	O
the	O
GPLv3	O
is	O
not	O
compatible	O
with	O
the	O
permissive	O
Apache	B-Application
license	I-Application
—	O
Apache	O
software	O
can	O
be	O
included	O
in	O
GPLv3	O
software	O
but	O
not	O
vice	O
versa	O
.	O
</s>
<s>
As	O
another	O
relevant	O
example	O
,	O
the	O
GPLv2	B-License
is	O
by	O
itself	O
not	O
compatible	O
with	O
the	O
GPLv3	O
.	O
</s>
<s>
The	O
2007	O
released	O
GPLv3	O
was	O
criticized	O
by	O
several	O
authors	O
for	O
adding	O
another	O
incompatible	O
license	O
in	O
the	O
FOSS	B-License
ecosystem.Are	O
you	O
sure	O
you	O
want	O
to	O
use	O
the	O
GPL	B-License
?	O
</s>
<s>
A	O
vanity	O
licenses	O
is	O
a	O
license	O
that	O
is	O
written	O
by	O
a	O
company	O
or	O
person	O
for	O
no	O
other	O
reason	O
than	O
to	O
write	O
their	O
own	O
license	O
(	O
"	O
NIH	O
syndrome	O
"	O
)	O
.Sharing	O
medical	O
software	O
:	O
FOSS	B-License
licensing	O
in	O
medicine	O
on	O
freesoftwaremagazine.com	O
by	O
Fred	O
Trotter	O
(	O
2007-06-14	O
)	O
If	O
a	O
new	O
license	O
is	O
created	O
that	O
has	O
no	O
obvious	O
improvement	O
or	O
difference	O
over	O
another	O
more	O
common	O
FOSS	B-License
license	O
it	O
can	O
often	O
be	O
criticized	O
as	O
a	O
vanity	O
license	O
.	O
</s>
<s>
As	O
of	O
2008	O
,	O
many	O
people	O
create	O
a	O
custom	O
new	O
license	O
for	O
their	O
newly	O
released	O
program	O
,	O
without	O
knowing	O
the	O
requirements	O
for	O
a	O
FOSS	B-License
license	O
and	O
without	O
realizing	O
that	O
using	O
a	O
nonstandard	O
license	O
can	O
make	O
that	O
program	O
almost	O
useless	O
to	O
others	O
.	O
</s>
<s>
In	O
July	O
2013	O
,	O
GitHub	B-Application
started	O
a	O
license	O
selection	O
wizard	O
called	O
choosealicense.GitHub	O
finally	O
takes	O
open	O
source	O
licenses	O
seriously	O
on	O
Infoworld	O
by	O
Simon	O
Phipps	O
on	O
July	O
2013	O
GitHub	B-Application
's	O
choosealicense	O
frontpage	O
offers	O
as	O
a	O
quick	O
selection	O
only	O
three	O
licenses	O
:	O
the	B-License
MIT	I-License
License	I-License
,	O
the	O
Apache	B-Application
License	I-Application
and	O
the	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
.	O
</s>
<s>
From	O
2006	O
Google	B-Protocol
Code	I-Protocol
only	O
accepted	O
projects	O
licensed	O
under	O
the	O
following	O
seven	O
licenses	O
:	O
</s>
<s>
One	O
year	O
later	O
,	O
around	O
2008	O
,	O
the	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
3.0	O
was	O
added	O
and	O
strongly	O
recommended	O
together	O
with	O
the	O
permissive	O
Apache	B-Application
license	I-Application
,	O
notably	O
excluded	O
was	O
the	O
AGPLv3	B-Application
to	O
reduce	O
license	O
proliferation.License	O
Proliferation	O
-	O
Less	O
is	O
More	O
,	O
One	O
is	O
Best	O
on	O
January	O
27th	O
,	O
2009	O
by	O
Ernest	O
M	O
.	O
Park	O
"	O
Chris	O
DiBona	O
from	O
Google	O
suffered	O
the	O
slings	O
and	O
arrows	O
of	O
the	O
OSS	O
community	O
when	O
he	O
rejected	O
the	O
AGPLv3	B-Application
license	O
for	O
Google	B-Protocol
Code	I-Protocol
repository	O
,	O
citing	O
license	B-License
proliferation	I-License
as	O
one	O
of	O
the	O
reasons.	O
"	O
</s>
<s>
Open	O
Source	O
Initiative	O
(	O
OSI	O
)	O
maintains	O
a	O
list	O
of	O
approved	O
licenses.OSI	O
Approved	O
Licenses	O
on	O
opensource.org	O
Early	O
in	O
its	O
history	O
,	O
the	O
OSI	O
contributed	O
to	O
license	B-License
proliferation	I-License
by	O
approving	O
vanity	O
and	O
non-reusable	O
licenses	O
.	O
</s>
<s>
In	O
2004	O
an	O
OSI	O
License	B-License
Proliferation	I-License
Project	O
was	O
startedLicense	O
Proliferation	O
Project	O
on	O
opensource.com	O
(	O
2004	O
)	O
has	O
prepared	O
a	O
License	B-License
Proliferation	I-License
Report	O
in	O
2007.License	O
Proliferation	O
Report	O
on	O
opensource.com	O
(	O
2007	O
)	O
The	O
report	O
defined	O
classes	O
of	O
licenses	O
:	O
</s>
<s>
The	O
group	O
of	O
"	O
popular	O
"	O
licenses	O
include	O
nine	O
licenses	O
:	O
Apache	B-Application
License	I-Application
2.0	I-Application
,	O
New	O
BSD	O
license	O
,	O
GPLv2	B-License
,	O
LGPLv2	B-Application
,	O
MIT	B-License
license	I-License
,	O
Mozilla	B-License
Public	I-License
License	I-License
1.1	I-License
,	O
Common	B-Application
Development	I-Application
and	I-Application
Distribution	I-Application
License	I-Application
,	O
Common	O
Public	O
License	O
,	O
Eclipse	B-License
Public	I-License
License	I-License
.	O
</s>
<s>
Richard	O
Stallman	O
,	O
former	O
president	O
of	O
Free	B-Operating_System
Software	I-Operating_System
Foundation	I-Operating_System
,	O
and	O
Bradley	O
M	O
.	O
Kuhn	O
,	O
former	O
Executive	O
Director	O
,	O
have	O
argued	O
against	O
license	B-License
proliferation	I-License
since	O
2000	O
,	O
when	O
they	O
instituted	O
the	O
FSF	O
license	O
list	O
,	O
which	O
urges	O
developers	O
to	O
license	O
their	O
software	O
under	O
GPL-compatible	O
free	O
software	O
license(s )	O
,	O
though	O
multiple	O
GPL-incompatible	O
free	O
software	B-License
licenses	I-License
are	O
listed	O
with	O
a	O
comment	O
stating	O
that	O
there	O
is	O
no	O
problem	O
using	O
and/or	O
working	O
on	O
a	O
piece	O
of	O
software	O
already	O
under	O
the	O
licenses	O
in	O
question	O
while	O
also	O
urging	O
readers	O
of	O
the	O
list	O
not	O
to	O
use	O
those	O
licenses	O
on	O
software	O
they	O
write.The	O
earliest	O
archived	O
version	O
of	O
the	O
license	O
list	O
reflects	O
this	O
position	O
.	O
</s>
<s>
Ciarán	O
O'Riordan	O
of	O
FSF	O
Europe	O
argues	O
that	O
the	O
main	O
thing	O
that	O
the	O
FSF	O
can	O
do	O
to	O
prevent	O
license	B-License
proliferation	I-License
is	O
to	O
reduce	O
the	O
reasons	O
for	O
making	O
new	O
licenses	O
in	O
the	O
first	O
place	O
,	O
in	O
an	O
editorial	O
entitled	O
How	O
GPLv3	O
tackles	O
license	O
proliferation.How	O
GPLv3	O
tackles	O
license	B-License
proliferation	I-License
on	O
linuxdevices.com	O
Generally	O
the	O
FSF	O
Europe	O
consistently	O
recommends	O
the	O
use	O
of	O
the	O
GNU	B-License
GPL	I-License
as	O
much	O
as	O
possible	O
,	O
and	O
when	O
that	O
is	O
not	O
possible	O
,	O
to	O
use	O
GPL-compatible	O
licenses	O
.	O
</s>
<s>
In	O
2005	O
Intel	O
has	O
voluntarily	O
retracted	O
their	O
Intel	B-License
Open	I-License
Source	I-License
License	I-License
from	O
the	O
OSI	O
list	O
of	O
open	O
source	O
licenses	O
and	O
has	O
also	O
ceased	O
to	O
use	O
or	O
recommend	O
this	O
license	O
to	O
reduce	O
license	B-License
proliferation	I-License
.	O
</s>
<s>
The	O
451group	O
created	O
in	O
June	O
2009	O
a	O
proliferation	O
report	O
called	O
The	O
Myth	O
of	O
Open	O
Source	O
License	O
Proliferation.The	O
Myth	O
of	O
Open	O
Source	O
License	B-License
Proliferation	I-License
on	O
the451group.com	O
A	O
2009	O
paper	O
from	O
the	O
University	O
of	O
Washington	O
School	O
of	O
Law	O
titled	O
Open	O
Source	O
License	B-License
Proliferation	I-License
:	O
Helpful	O
Diversity	O
or	O
Hopeless	O
Confusion	O
?	O
</s>
<s>
called	O
for	O
three	O
things	O
as	O
a	O
solution	O
:	O
"	O
A	O
Wizzier	O
Wizzard	O
"	O
(	O
for	O
license	O
selection	O
)	O
,	O
"	O
Best	O
Practices	O
and	O
Legacy	O
Licenses	O
"	O
,	O
"	O
More	O
Legal	O
Services	O
For	O
Hackers	O
"	O
.Open	O
Source	O
License	B-License
Proliferation	I-License
:	O
Helpful	O
Diversity	O
or	O
Hopeless	O
Confusion	O
?	O
</s>
<s>
on	O
law.washington.edu	O
by	O
Robert	O
W	O
.	O
Gomulkiewicz	O
on	O
2009	O
The	O
OpenSource	O
Software	O
Collaboration	O
Counseling	O
(	O
OSSCC	O
)	O
recommends	O
,	O
based	O
on	O
the	O
originally	O
nine	O
recommended	O
OSI	O
licenses	O
,	O
five	O
licenses	O
:	O
the	O
Apache	B-Application
License	I-Application
2.0	I-Application
,	O
New	O
BSD	O
License	O
,	O
CDDL	B-Application
,	O
MIT	B-License
license	I-License
,	O
and	O
to	O
some	O
degree	O
the	O
MPL	O
,	O
as	O
they	O
support	O
collaboration	O
,	O
grant	O
patent	O
use	O
and	O
offer	O
patent	O
protection	O
.	O
</s>
