Tridge on ‘Patent defence for open source projects’. Watch it! Some key elements:

• prior art defence is very very hard – ‘non infringement’ is a much better defense because you only need to show you don’t do the independent claims.
• Reading a patent doesn’t really harm us because triple damages is no less fatal than single damages Reading patents to avoid them is a good idea.
• Dealing with patents is very technical. It needs training (and the talk has that training)
• Patents are hard to read.
• Claims are often interpreted much more specifically than engineers expect.
• Best prior art is our own source code, with VCS date records and the exact date often matters because of the riority date.
• Invalidation: dead patents are vampires… and when they come back they are harder to kill again. Read the file wrapper – audit log containing all correspondence <-> patent office and applicant.
• Patents are not code: judges can vary the meaning.
• Claim charts are what you use to talk to patent lawyers.
• Build workarounds *and publish them*. Encourage others to adopt them.