BAA: Heathrow, Gatwick, Stansted, Southampton, Glasgow, Edinburgh, Aberdeen.
Manchester Airport Group: Manchester, Bournemouth, Nottingham-EMA
Peel Holdings: Durham/Tees, Liverpool, Doncaster, Sheffield (they also own the Trafford Centre)
Majority Local Authority Ownership: Newcastle (with Copenhagen), Birmingham (with Aer Rianta), Luton (operated by Abertis/Aena), Exeter, Humberside, Blackpool
Maquarie & Cintra: Bristol
TBL plc: Cardiff
doubtless I've missed some, but I think that's most of the major ones.