Lars Forberg, a Non-Executive Director of Alent, this week topped up his stake in the company with three rounds of share purchases.The group, which supplies consumable specialty chemicals and engineered materials, reported that Forberg bought 49,000 shares at 311p for £152,390 on November 18th, followed by a further 35,000 the following day, bought at 316p. By far the largest purchase was made on Thursday, when he acquired 4.21m shares at 325p a piece, taking his total holding to just short of 60m shares. The FTSE 250 company, which was demerged from Cookson in December 2012, announced earlier this month that trading since July had been "slightly" below its expectations due to softer demand in consumer electronics end-markets, having in August said it was positioned "to grow NSV and to improve margins on higher volumes during the second half".It also said full-year net sales value would be flat for the full year due to fewer people buying personal computers.For that same time period management stressed that visibility remained limited as consumer electronics end-markets were showing "more muted seasonal pick-up" in demand and NSV was expected to be "around the same levels as 2012 with slightly unfavourable product mix", which will presumably dent profit margins.Top Director BuysAlent (ALNT) Director name: Mr Lars FörbergAmount purchased: 49,000 @ 311.00p Value: £152,390AimShell Acquisitions (ASAP) Director name: Mr James Anthony LeekAmount purchased: 154,630 @ 32.50p Value: £50,255HICL Infrastructure Company Ltd (HICL) Director name: Mr Ian RussellAmount purchased: 37,880 @ 132.00p Value: £50,002Bellway (BWY) Director name: Mr Paul Hampden SmithAmount purchased: 3,576 @ 1,398.00p Value: £49,992Prudential (PRU) Director name: Mr Philip RemnantAmount purchased: 2,609 @ 1,257.85p Value: £32,817AimShell Acquisitions (ASAP) Director name: Mr James Anthony LeekAmount purchased: 90,240 @ 32.50p Value: £29,328Senior (SNR) Director name: Mrs Celia Baxter Amount purchased: 10,000 @ 282.17p Value: £28,217Top Director SellsG4S (GFS) Director name: Mr Grahame GibsonAmount sold: 100,000 @ 264.70p Value: £264,700Fenner (FENR) Director name: Mr Richard John PerryAmount sold: 17,433 @ 445.83p Value: £77,722Avon Rubber (AVON) Director name: Ms Stella J PirieAmount sold: 9,710 @ 580.00p Value: £56,318Fenner (FENR) Director name: Mr Nick Hobson Amount sold: 10,788 @ 445.83p Value: £48,096Fenner (FENR) Director name: Mrs Debra BradburyAmount sold: 5,325 @ 445.83p Value: £23,740NR