Investment holding firm Newmark Security said non-executive chairman Maurice Dwek purchased over 5.78m shares in the group.He paid 1p per share and increased his total stake to 59m shares, representing 13.12% of the group.Non-executive director Alexander Reid purchased 5m at the same price to increase his stake to 82m shares, which represents 18.35% of the group.Another non-exec, Alexander Reid made a maiden purchase of 720,000 shares at the same price.Top Director BuysBrambles Ld (BXB) Director name: Mr Brian SchwartzAmount purchased: 10,000 @ 298.50p Value: £29,850Newmark Security PLC (NWT) Director name: Mr Maurice DwekAmount purchased: 5,780,000 @ 1.00p Value: £57,800Newmark Security PLC (NWT) Director name: Mr Alexander ReidAmount purchased: 5,000,000 @ 1.00p Value: £50,000Camper & Nicholsons Marina Investments Ltd. (CNMI) Director name: Mr Nicholas MarisAmount purchased: 250,000 @ 18.00p Value: £45,000W H Ireland (WHI) Director name: Mr Richard FordAmount purchased: 50,000 @ 60.00p Value: £30,000Kofax (KFX) Director name: Mr Christopher J ConwayAmount purchased: 25,000 @ 120.00p Value: £30,000National Grid (NG.) Director name: Mr John M AllanAmount purchased: 5,000 @ 580.00p Value: £29,000Oxford Catalysts (OCG) Director name: Mr Roy S LipskiAmount purchased: 87,273 @ 33.00p Value: £28,800Norcon (NCON) Director name: Mr Arnold RørholtAmount purchased: 40,000 @ 72.00p Value: £28,800Top Director SellsDairy Farm International (Singapore) (DFI) Director name: Mr Michael KokAmount sold: 27,000 @ $5.20 Value: $140,400