The Plessey Company plc was a British-based international electronics, defence and telecommunications company. It originated in 1917, growing and diversifying into electronics. It expanded after the second world war by acquisition of companies and formed overseas companies. Plessey produced an early Integrated Circuit model in 1957, before the patents of Jack St. Clair Kilby of Texas Instruments and Robert Noyce of Fairchild . It was listed on the London Stock Exchange and was a constituent of… (More on Plessey)