(ShareCast News) - Tullow Oil director Jeremy Wilson has increase his in the company, hours after it posted a $1.09bn (£752.6m) loss for 2015.Wilson purchased 30,000 shares for nearly £44,000 in a bid to give the market confidence about the company's future.It takes his total holding to 45,000 shares, a stake of 0.005%.In its results for the year to 31 December 2015, the FTSE 250 oil and gas exploration and production group said revenues had fallen 27% for the year from $2.21bn in 2014 to $1.61bn, due to the fall in oil prices.Its pre-tax operating cash flow also fell 38% from $1.55bn to $967m while gross profit fell 46% from $1.10bn to $591m.However the company had pegged back its full-year loss from $1.97bn to $1.09bn in 2015.It said Tullow has focused on cost savings, improved efficiencies, and a lower capital expenditure, for which it is aiming to cut another $1.1bn of capex in 2016.Chief executive Aidan Heavey said 2016's challenge is to be "equally robust" in responding to remaining uncertainties.Top Director BuysJudges Scientific (JDG)Director name: Cicurel,DavidAmount purchased: 9,275 @ 1,675.00pValue: £155,356.25Banco Santander S.a. (BNC)Director name: Botin,Francisco JavierAmount purchased: 50,000 @ 271.49pValue: £135,745Banco Santander S.a. (BNC)Director name: Botin,Francisco JavierAmount purchased: 50,000 @ 270.94pValue: £135,470Tullow Oil (TLW)Director name: Wilson,Jeremy Amount purchased: 30,000 @ 145.47pValue: £43,641.00Brewin Dolphin Holdings (BRW)Director name: Miller,Simon Edward CallumAmount purchased: 10,000 @ 254.90pValue: £25,490.00Electra Private Equity (ELTA)Director name: Bramson,EdwardAmount purchased: 550 @ 3,409.00pValue: £18,749.50Cohort (CHRT)Director name: Walmsley,Sir RobertAmount purchased: 4,965 @ 332.00pValue: £16,483.80Northgate (NTG)Director name: Caseberry ,Jill Amount purchased: 5,000 @ 329.11pValue: £16,455.50Redrow (RDW)Director name: Lyons,MichaelAmount purchased: 3,000 @ 397.76pValue: £11,932.80Diageo (DGE)Director name: Humer,Franz BAmount purchased: 462 @ 1,793.00pValue: £8,283.66Henderson Far East Income Ltd. (HFEL)Director name: Chapman,JuliaAmount purchased: 2,616 @ 267.29pValue: £6,992.40Phsc (PHSC)Director name: King,Stephen AAmount purchased: 15,000 @ 24.00pValue: £3,600.00Asian Total Return Investment Company (ATR)Director name: Keljik,Christopher AAmount purchased: 1,041 @ 191.15pValue: £1,989.87Bp (BP.)Director name: Gilvary,BrianAmount purchased: 95 @ 334.45pValue: £317.73Diageo (DGE)Director name: Mikells,KathrynAmount purchased: 10 @ 1,793.00pValue: £179.30Interserve (IRV)Director name: Melizan,BruceAmount purchased: 36 @ 420.00pValue: £151.20Countrywide (CWD)Director name: Clarke,JimAmount purchased: 40 @ 377.09pValue: £150.84Taylor Wimpey (TW.)Director name: Jordan,James JAmount purchased: 82 @ 182.80pValue: £149.90Taylor Wimpey (TW.)Director name: Redfern,PeterAmount purchased: 82 @ 182.80pValue: £149.90Interserve (IRV)Director name: Haywood,TimAmount purchased: 35 @ 420.00pValue: £147.00Interserve (IRV)Director name: Ringrose,Adrian MAmount purchased: 30 @ 420.00pValue: £126.00Interserve (IRV)Director name: Dance,StevenAmount purchased: 30 @ 420.00pValue: £126.00Imi (IMI)Director name: Twite,RoyAmount purchased: 16 @ 777.00pValue: £124.32Imi (IMI)Director name: Shook ,Daniel Amount purchased: 16 @ 777.00pValue: £124.32Imi (IMI)Director name: Selway,Mark WAmount purchased: 16 @ 777.00pValue: £124.32Glaxosmithkline (GSK)Director name: Dingemans,SimonAmount purchased: 9 @ 1,368.63pValue: £123.18Glaxosmithkline (GSK)Director name: Witty,Sir Andrew PAmount purchased: 9 @ 1,368.63pValue: £123.18There were no director sells at the time of publication