As Ed says Bob. The inventor of the Channel ock what ever that is would have either sold his invention to someone, manfacured it himself, or licienced somone to produce and market it.
You buy it you are free to do what you like with it.
If the Plumber or Electrician decided he wasn't going to fork out money for one and made his own to the same spec as the original, or even with very little variation actually, he would be open to get his butt sued off because he is in breach of patient law.
Mind you. An artist can buy songs from some writers.
Then he can sing them to his little heart's cotent and even submit them on his PRO playist and get the live play royalty cheque himself.
Graham


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