Patents absolutely are a block if you need to be compatible with a patented system.
Due to the Berne convention, we don't get to have that comparison. Although lots of people argue that China's weak enforcement of non-Chinese IP has had rather a positive influence on their industry.
There's a good history of patents and cartelisation in "Information Feudalism" http://www.amazon.co.uk/Information-Feudalism-Owns-Knowledge...