Enquest's chief executive Amjad Bseisu has been increasing his stake in the FTSE 250-listed North Sea oil and gas group, spending nearly £3m on shares.Double A, "a discretionary Trust in which the extended family of Amjad Bseisu have a beneficial interest" took about 2.44m shares at 121.6p a time yesterday, the company announced today. Double A now has about 53.4m shares or 6.7% of the company. Meanwhile, Alima Trust, another trust "in which the Bseisu family has a beneficial interest" has about 9.2m shares.The shares have declined since earlier in June when Double A took nearly 8m shares at more than 130p a pop.Enquest's chairman James Buckee has also been taking advantage of the recent weak spell in Enquest's share price to up his stake. He bought 100,000 shares at 123.35p a time and now has nearly 882,000.Top Director BuysGlaxoSmithKline (GSK) Director name: Mr Tom De SwaanAmount purchased: 875,947 @ 1,320.00p Value: £11,562,500EnQuest (ENQ) Director name: Mr Amjad BseisuAmount purchased: 2,442,004 @ 121.59p Value: £2,969,233Ultra Electronics Holdings (ULE) Director name: Mr Rakesh SharmaAmount purchased: 39,833 @ 1,708.00p Value: £680,348EnQuest (ENQ) Director name: Dr James BuckeeAmount purchased: 100,000 @ 123.35p Value: £123,350Tesco (TSCO) Director name: Mr Jacqueline Tammenoms BakkerAmount purchased: 16,472 @ 409.76p Value: £67,496Melrose Resources (MRS) Director name: Mr Robert F M AdairAmount purchased: 20,000 @ 227.00p Value: £45,400GlaxoSmithKline (GSK) Director name: Mr Lawrence CulpAmount purchased: 1,955 @ 2,121.50p Value: £41,475GlaxoSmithKline (GSK) Director name: Sir Sir Deryck MaughanAmount purchased: 1,955 @ 2,121.50p Value: £41,475GlaxoSmithKline (GSK) Director name: Dr Dr Dan PodolskyAmount purchased: 1,885 @ 2,121.50p Value: £39,990GlaxoSmithKline (GSK) Director name: Sir Sir Christopher GentAmount purchased: 2,557 @ 1,320.00p Value: £33,752Top Director SellsInternational Consolidated Airlines Group SA (IAG) Director name: Mr Keith WilliamsAmount sold: 13,621 @ 252.30p Value: £34,366