IGas Energy, a British onshore oil and gas explorer and developer, was one of the top risers on AIM on Thursday as Chief Executive Andrew Austin dipped into the market.Austin shelled out £0.4m on 300,000 shares at 135.38p, even though the shares are trading around all-time highs. The purchase indicates Austin's optimism about prospects after Monday saw IGas and partners Egdon Resources, Dart Energy and eCorp sign a farm-out agreement with French oil giant Total to sell a 40% interest in the UK Onshore Petroleum exploration and development licences PEDL139 and PEDL140 in Lincolnshire's Gainsborough Trough.To fund the share purchase, the CEO took out a loan facility, and has transferred up to 7.5m shares as security. He cannot sell the shares during the term and is required to redeem the shares at maturity when the loan is repaid at the end of the three-year term and it is his full intention to do so, a statement from the company said. Top Director BuyseXpansys (XPS) Director name: Mr Peter Jones CBEAmount purchased: 110,250,320 @ 0.53p Value: £584,327IGas Energy (IGAS) Director name: Mr Andrew AustinAmount purchased: 300,000 @ 135.38p Value: £406,140North Atlantic Smaller Companies Inv Trust (NAS) Director name: Mr Christopher H B MillsAmount purchased: 7,500 @ 1,555.00p Value: £116,625Northern Petroleum (NOP) Director name: Mr Jonathan MurphyAmount purchased: 325,200 @ 30.75p Value: £99,999Majedie Investments (MAJE) Director name: Mr Andrew AdcockAmount purchased: 30,000 @ 205.00p Value: £61,500Electra Private Equity (ELTA) Director name: Mr Francesca Barnes Amount purchased: 500 @ 2,402.70p Value: £12,014Sabien Technology Group (SNT) Director name: Mr Karl Upton MonaghanAmount purchased: 32,594 @ 35.10p Value: £11,440Top Director SellsUK Mail Group (UKM) Director name: Mr Guy BuswellAmount sold: 70,000 @ 652.50p Value: £456,750Miton Group (MGR) Director name: Mr Martin Gray Amount sold: 760,000 @ 45.96p Value: £349,296Sabien Technology Group (SNT) Director name: Mr Karl Upton MonaghanAmount sold: 32,940 @ 35.00p Value: £11,529