First of all, I am not a lawyer, but I have talked to lawyers, but
finding a lawyer who is willing to be quoted publicly without paying
them is difficult.
There are several things that can be meant went saying MP3 decoding
because there are several things that MP3 can be.
The MPEG-1 specification was publish in 1993 as ISO/IEC 11172. It
include both video and audio codecs.
Most of the MP3 files I have seen on the internet are MPEG-1 layer III
audio. The linux file command will identify these as:
MPEG ADTS, layer III, v1
The MPEG-2 specification also had layer III audio. The linux file
command will identify these as:
MPEG ADTS, layer III, v2
There is also a non-ISO MP3 file format that is called MPEG-2.5 created
by Fraunhofer IIS.
Now for patent status.
MPEG-1 Layer III audio decoding is possible to do patent free in the US
as of September 2015 assuming you do decoding in roughly the way
described in the MPEG-1 specification.
MPEG-1 Layer III audio encoding is probably possible to do patent free.
That said there are patents that can apply to the encoding that expire
in the 2017 timeframe. See for example US patent 6009399.
MPEG-2 Layer III audio decoding and encoding may be patented or not.
Many of the MPEG-2 patents don't expire until 2018, so it would take
some work to determine if MPEG-2 Layer III can be decoded or encoded
MPEG-2.5 is still patented for decoding and encoding and will be till at
The patents that Eric Smith is referring to that expire in February 2017
and April 2017 are by Sisvel and I believe they are U.S. Patent
;, which expires
February 2017, U.S. Patent 5,850,456
;, which expires February 2017
and U.S. Patent 5,960,037 <https://www.google.com/patents/US5960037>
which expires 9. April 2017. These were filed in 1997 so it is highly
unlikely that they read on MPEG-1 Layer III audio decoding since the
MPEG-1 specification was publish in 1993 (and therefore the patents
would not be valid against MPEG-1 since the filing date is more than 1
year after the specification was published).
The patent that 'expires' in December 2017 I believe is U.S. Patent
but I think that
actually expired in 2014/12/30 (17 years after grant date of December
30, 1997) because it was filed November 18, 1996 but is a continuation
of a PCT/DE93/00448 filed in May 18, 1993. Redhat lists this as
expiring in November 18, 2016 (Possibly this November 2016 date is why
MPEG-1 Layer III audio decoding is only happening now, instead of last
(See also my previous email:
So an MPEG-1 Layer III decoding program can probably be used patent free.
Date: Thu, 10 Nov 2016 14:55:06 -0700
From: Eric Smith <spacewar(a)gmail.com>
Subject: [Fedora-legal-list] MP3 status?
Content-Type: text/plain; charset=UTF-8
About three hours ago on Twitter @spotrh tweeted:
"As of today, MP3 decoding software is permissible in Fedora."
Is this true? If so, could we have a bit more detail?
I'm slightly suspicious as to the authenticity of the tweet because
yesterday @spotrh tweeted:
"I'm going to stay off social media for the foreseeable future. If you
need me, you know how to find me."
There are MP3-related US patents with expirations in September 2015,
February 2017, April 2017, and December 2017, and some people argue that
the last one affecting decoding may have been the one that expired in
September 2015, but I don't know of anything that changed in 2016.