G4S leapt into the top spot after winning a deal to provide security at the two day Northern Ireland G8 Summit in June. It will provide 450 staff members to give support to the police.Antofagasta was another strong riser, erasing some of last week's losses after Nomura said it was one of several miners to have "significant balance sheet headroom". Capita Group climbed after Espirito Santo increased its target price from 700p to 900p and upgraded the stock to neutral. Meanwhile, Standard Chartered fell into the red following reports that short seller Carson Block is betting against the company's debt, saying its loan quality is "deteriorating", and that the market "misunderstands the amount of risk that's presently in the book".Part-nationalised lender Lloyds was also in decline after it revealed that Chairman Sir Winfried Bischoff will retire within a year's time, a move thought to be in anticipation of the bank's potential privatisation. IAG was in the red following Friday's first quarter loss result, and despite UBS saying it sees more upside in the company.FTSE 100 - RisersG4S (GFS) 257.00p +3.75%Antofagasta (ANTO) 940.00p +2.96%Capita (CPI) 943.00p +2.33%BAE Systems (BA.) 387.10p +1.95%Weir Group (WEIR) 2,391.00p +1.83%Sainsbury (J) (SBRY) 389.00p +1.78%Serco Group (SRP) 634.50p +1.60%Babcock International Group (BAB) 1,090.00p +1.49%Morrison (Wm) Supermarkets (MRW) 292.90p +1.42%Randgold Resources Ltd. (RRS) 5,080.00p +1.40%FTSE 100 - FallersStandard Chartered (STAN) 1,538.50p -2.81%Lloyds Banking Group (LLOY) 57.79p -1.95%International Consolidated Airlines Group SA (CDI) (IAG) 270.70p -1.88%Aviva (AV.) 318.70p -1.45%BT Group (BT.A) 305.10p -1.42%Carnival (CCL) 2,363.00p -1.42%GKN (GKN) 287.10p -1.27%Aberdeen Asset Management (ADN) 459.60p -1.12%Barclays (BARC) 310.95p -1.10%Anglo American (AAL) 1,574.00p -1.07%NR