LONDON -- The FTSE 100 (INDEX: ^FTSE), hovering around 5,660 points, looks like it's slowly moving in the direction of its 52-week high of 5,966 points, attained on March 16. And while it's not time to cheer yet, that's still good progress from its Oct. 4 low of 4,944.

But however long it takes the FTSE to reach a new high, a number of individual shares have been headed skyward of late. Here are three big gainers this month.

Aegis (LSE: AGS.L)
Media group Aegis is up a massive 46% on the month, gaining 74.6 pence to reach 235.6 pence.

The reason is clear: The firm has agreed to a takeover offer from Japanese advertising giant Dentsu, which has offered 240 pence per share. That's a 48% premium on the closing price of June 11, the day before the offer was announced.

The deal will create one of the world's largest advertising groups, and it will have rewarded Aegis shareholders handsomely -- the shares were barely above 50 pence at the start of 2009.

GKN (LSE: GKN.L)
Shares in engineer GKN are up 18% to 213 pence on the month so far after the company announced a deal to buy up Volvo Aero on July 5. It will give GKN a finger in lots of aviation engineering pies, with Volvo components going into most aero engines these days.

The acquisition of the aero division of AB Volvo is valued at 633 million pounds and comes at a time when aviation demand is expected to rise; only last week, Boeing (NYSE: BA) announced a new order for 150 of its 737 series planes from United Airlines, including 100 of the new, fuel-efficient 737 Max model.

Quintain Estates (LSE: QED.L)
After slumping to a 52-week low in mid-June, Quintain Estates shares have enjoyed a boost of 36% to 44 pence since that low point, including 16% since the start of July.

The firm got a welcome boost from Hong Kong's Knight Dragon investment firm (run by billionaire Henry Chung Kar-Shun), which has taken a 60% stake in London's Greenwich Peninsula property development. The deal is expected to land Quintain around 70 million pounds from project management fees and other sources over six years, on top of profits from its share of ownership.

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