Shares in payment processor Worldpay jumped by 27.7% after it said it had received takeover approaches.
Following reports that it could be a bid target, Worldpay confirmed it had been approached by both Vantiv and JPMorgan Chase Bank.
Despite the jump in Worldpay shares, the FTSE 100 index closed down 19.86 points at 7,357.23 by late morning.
Shares in Sainsbury’s rose 0.3% after its latest sales figures came in slightly ahead of expectations.
The UK’s second largest supermarket chain – which also owns Argos – said like-for-like sales excluding petrol rose 2.3% in the 16 weeks to 1 July.
Outside the FTSE 100 index, shares in Imagination Technologies rose 9.4% after the company – which is up for sale and in dispute with Apple, its largest customer – said it had returned to profit.
The company reported a £2.4m pre-tax profit for 12 months to 30 April, compared with a £29.4m loss in the previous year. Revenues rose 19% to £145.2m.
On the currency markets, the pound was down 0.17% against the dollar at $1.2918 and was flat against the euro at 1.1386 euros.