Private company
Plessey
British electronics, defence and telecommunications company
The Plessey Company plc was a British electronics, defence and telecommunications company. It was listed on the London Stock Exchange and was a constituent of the FTSE 100 Index until it was acquired by GEC and Siemens in 1989.2 Wikipedia text CC BY-SA 4.0
Last updated Oct 21, 2026.
Overview
- Industryelectronics1
- HeadquartersIlford1
- Websiteplesseysemiconductors.com
- Legal formpublic limited company1
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The Plessey Company plc was a British electronics, defence and telecommunications company. It was listed on the London Stock Exchange and was a constituent of the FTSE 100 Index until it was acquired by GEC and Siemens in 1989.2
Corporate structure
Plessey sits at the top of its group. 2 entities, 2 countries on record. Switch between the flow chart and the network, and select any entity to see its details.
- Plessey Ilford
- Plessey Valdarno Subsidiary ยท Terranuova Bracciolini, Italy
Built from subsidiaries, stakes and holdings from Wikidata (CC0); major holders from Schedules 13D and 13G. Each entity in the chart links to its source.
Subsidiaries and ownership
Subsidiaries
- Plessey Valdarno
From Wikidata.1
Timeline
Links
- Websiteplesseysemiconductors.com1
- WikipediaPlessey
- More imagesWikimedia Commons
- WikidataQ7204713
Sources
The numbers on this page point here. Each one links to the record it came from.
- 1WikidataPlessey on Wikidata
- 2WikipediaPlessey on Wikipedia
- 3Wikimedia CommonsPlessey photo by The wub, CC BY-SA 4.0