The trouble with most software patents is that they don't represent technology invented by companies with the purpose of selling that technology. They are made

The trouble with most software patents is that they don't represent technology invented by companies with the purpose of selling that technology. They are made by companies doing some other business, and to put road-blocks in front of potential competitors. Admittedly this is less true for encoding patents, some of which are held by research-oriented organisations that then charge royalties to the companies which deploy the tech.