London’s FTSE 250 was 1.3% firmer at 20,188.07 in afternoon trade on Thursday.
Government contractor Serco surged as it lifted its full-year guidance following better-than-expected trading in the first four months of the year.
FirstGroup racked up strong gains after saying it was considering a takeover offer from private equity firm I Square, which owns Irish energy supplier Energia. In a statement responding to a spike in the share price, the transport operator said it had received a series of unsolicited, conditional takeover proposals from I Squared.
Investment platform AJ Bell was also in the back after it reported a drop in interim pre-tax profit as dealing activity normalised, but lifted its margin guidance for the year.
Transact owner IntegraFin slumped, with analysts pointing to a downbeat outlook in the company’s first-half results.
Johnson Matthey fell after saying it expects its full-year operating performance to be in the lower half of the consensus range.
Centrica and Drax also declined after Chancellor Rishi Sunak announced a £5bn windfall tax on energy firms.
FTSE 250 – Risers
Serco Group (SRP) 166.80p 9.16%
Aston Martin Lagonda Global Holdings (AML) 667.40p 8.70%
FirstGroup (FGP) 129.70p 8.63%
Marks & Spencer Group (MKS) 149.75p 8.01%
AJ Bell (AJB) 275.00p 7.76%
Carnival (CCL) 949.00p 7.30%
Currys (CURY) 85.25p 6.03%
Trainline (TRN) 323.60p 5.75%
Auction Technology Group (ATG) 1,030.00p 5.64%
Mitchells & Butlers (MAB) 208.60p 5.51%
FTSE 250 – Fallers
IntegraFin Holding (IHP) 286.40p -18.03%
Johnson Matthey (JMAT) 2,179.00p -7.32%
Centrica (CNA) 80.36p -5.81%
Petrofac Ltd. (PFC) 147.40p -4.60%
Wizz Air Holdings (WIZZ) 2,982.00p -2.83%
Pennon Group (PNN) 1,040.00p -2.44%
Drax Group (DRX) 700.00p -2.37%
Vivo Energy (VVO) 139.40p -2.24%
Centamin (DI) (CEY) 84.16p -1.93%
Energean (ENOG) 1,347.00p -1.68%