(Sharecast News) - Johnson Matthey chairman, Patrick Webster Thomas, picked-up a large batch of shares in the company he helps run.On Monday, Thomas bought 4,257 shares at 3,038p apiece, for a total transaction amount of £129,336.59, the company said in a statement.Roughly two months before, on 21 November, the specialty chemicals manufacturer had posted a 19% jump in first half pre-tax profits to reach £244m on revenue of £7.1bn, which was up 10% from the same period a year ago.Management also said full-year operating performance would be towards the upper end of its guidance for mid to high single digit growth.A recent rally in the share price had returned the stock to its best level for two months, but it remained well below its 52-week highs.At the turn of the year, on 3 January, analysts at Deutshe Bank cut their target price for the shares from 4,500p to 3,700p, blaming lower medium and longer-term profit estimates for the company.However, the company's fundamental growth drivers remained "intact", they said.Those reductions to its estimates "mostly reflect further (diesel) share declines post 2025, as well as a medium- and long term accelerated pick up in powertrain electrification", the German broker said.In the near-term meanwhile, a further slowdown in auto production volumes was anticipated in 2019."Despite a flurry of headlines around diesel declines and softness in automotive markets, we note that the fundamental growth drivers remain intact and the company is on track to deliver against its FY and mid-term guidance."Top Director BuysObtala Limited (OBT)Director name: Dolan,Paul TiernanAmount purchased: 30,000,000 @ 6.50pValue: £1,949,999.93Johnson Matthey (JMAT)Director name: Thomas,Patrick W.Amount purchased: 4,257 @ 3,038.21pValue: £129,336.60Aberdeen Diversified Income And Growth Trust (ADIG)Director name: Grover,Jim Amount purchased: 100,000 @ 115.00pValue: £115,000.00Martin Currie Asia Unconstrained Trust (MCP)Director name: Cleland,CraigAmount purchased: 7,500 @ 372.66pValue: £27,949.50Regency Mines (RGM)Director name: Bell,AndrewAmount purchased: 7,000,000 @ 0.38pValue: £26,299.00U And I Group (UAI)Director name: Upton,RichardAmount purchased: 11,720 @ 205.00pValue: £24,026.00Volution Group (wi) (FAN)Director name: Reading,Anthony JAmount purchased: 5,000 @ 144.96pValue: £7,248.00Henry Boot (BOOT)Director name: Jennings,GeraldAmount purchased: 2,000 @ 259.00pValue: £5,180.00Jupiter Emerging & Frontier Income Trust Red (JEFI)Director name: Moakes,NicholasAmount purchased: 5,172 @ 96.66pValue: £4,999.26Applied Graphene Materials (AGM)Director name: Blain,DavidAmount purchased: 17,800 @ 28.00pValue: £4,984.00Rotork (ROR)Director name: Davis,JonathanAmount purchased: 526 @ 273.06pValue: £1,436.30Scottish Mortgage Inv Trust (SMT)Director name: Subacchi ,Paola Amount purchased: 102 @ 488.50pValue: £498.27Rio Tinto (RIO)Director name: Jacques,Jean-SébastienAmount purchased: 10 @ 3,890.12pValue: £389.01Rio Tinto (RIO)Director name: Jacques,Jean-SébastienAmount purchased: 10 @ 3,890.12pValue: £375.00Baillie Gifford Shin Nippon (BGS)Director name: Donaldson,Michael NeilAmount purchased: 71 @ 174.50pValue: £123.90Rio Tinto (RIO)Director name: Jacques,Jean-SébastienAmount purchased: 10 @ n/aValue: n/aTop Director SellsObtala Limited (OBT)Director name: Pelham,Miles CAmount sold: 30,000,000 @ 6.50pValue: £1,949,999.93Bellway (BWY)Director name: Honeyman,JasonAmount sold: 6,281 @ 2,932.00pValue: £184,158.92Numis Corporation (NUM)Director name: Holloway,Andrew Mark Amount sold: 4,861 @ 240.50pValue: £11,690.70