Frequently asked questions about patents and free telephony

FAQ

Steve Underwood

documentation in progress

This document can be freely redistributed according to the terms of the GNU General Public License.


Table of Contents

Isn't it wrong that people can keep these patents secret?
If I implement something in software outside the USA, I am free from patent problems. Right?
If I build a clean room implementation of some software, I have no patent problems. Right?
If I build a clean room implementation of some software, I have no trade secret problems. Right?
I don't know of any patents applicable to what I am doing, so I am OK. Right?
Software patents only exist in the USA, so I can freely use things like G.729 in Europe. Right?
If I wish really hard, and twist everything people say, then I can come to the conclusion that patents on things like voice compression techniques don't apply to me. Right?
I cannot use the GPL licence on something like a G.729 implementation, because it is patented. Right?
What if I implement something which is patented, purely to teach myself about the subject?
Nobody has pressed any claims so far, so it must be OK. Right?
There is lots of prior art for what I am doing, so I can ignore the bogus patents. Right?
I've read the patent standing in my way, and its full of stuff that is clearly old hat. How can they patent that?
I've read the patent standing in my way, and I only infringe a few of its claims. Does that mean I am OK?
How come publicly available standards have been tied to patented techniques? Doesn't this give the patent holders a monopoly position?
I often see the term "prior art" in relation to patents. What does it mean?
You can't patent pure maths. Compression is pure maths, so how can it be patented?
Software cannot be patented in the EU, right?
Can I freely distribute software using patented techniques in the EU? The software on its own doesn't do anything, right?
If the European Patent Office has issued patents which contravene the rules, can I ignore them?

Patents are a significant problem for freely implemented VoIP systems. This is mostly because the potential profits from mobile communications provoked a frenzy of patenting anything related to voice processing in the 1990s. A lot of people spout a lot of misinformed rubbish about this. The same questions, and wrong answers, keep getting passed around. Its time for an FAQ.

I am not a lawyer. Treat this FAQ only as an outline guide, based on knowledge gained through years of engineering. Do not assume anything in the FAQ is completely reliable. Even if I were a lawyer, it would still be impractical to write an FAQ reliable in all countries and over time.

Isn't it wrong that people can keep these patents secret?

This is a very odd misconception some people have. The word patent actually means open. When you patent a technique you openly publish it. In return, the government offers you legal protection against other people using the same idea for a limited period. This is usually 15 to 20 years, depending on the country and other circumstances. Many countries make the text of all patents freely available for inspection on a web site. Still, some people have this strange notion that a patent is some form of secret.

A small number of patents are, in fact, kept secret in some countries. These are for techniques considered to have military potential.