The skilled person and the common general knowledge
16.It was agreed that the skilled person is an engineer engaged in the design and manufacture of plastic packaging for products such as foodstuffs. There was no dispute of significance regarding the skilled person’s common general knowledge and it is not necessary for me to set that out in detail save for one matter. 17.Unusually, it was common ground that there was a relevant long felt want among those in the plastics industry. Both sides relied on it. It arose from the tendency for the seal between lidding film and plastic containers, especially transparent PET trays for food, to be unreliable. Alternatively, if the seal was improved by using multi-layered plastic to make the containers, the consequence was higher cost and skeletal waste. There was a long felt want for a better solution to sealing lidding film onto containers. All parties agreed that the skilled person would have been aware of that gap in the market.