John Whittaker paid £5.1m to add 1.5m shares to his stake in shopping centres group Intu Properties.
Whittaker is chairman of Peel and non-executive non-independent deputy chairman of Intu, owner of the Intu Trafford Centre. He spent £3.4m in one transaction on Wednesday 11 March and invested a further £1.7m on Thursday 12 March.
Whittaker and his associated companies now own 22% of the group. Intu Properties is valued at £4.5bn, valuing Whittaker's stake at £1bn.
Intu's assets include five regional centres: Trafford Centre, Lakeside, Metrocentre, Braehead and Cribbs Causeway. There are also town and city centre malls including Manchester Arndale, St David's, Eldon Square, Watford, Victoria Centre, Midsummer Place, Chapelfield, Uxbridge, Potteries and Bromley.
Shares in Intu were priced at 345p, up 3p at 3.40pm on Monday.