A share purchase by Nicholas Brigstocke, the Non-Executive Chairman of 3D solutions company DDD, prompted shares to jump by around a fifth on Friday. Brigstocke acquired 200,000 shares of the company at an average purchase price of 5.69p in transactions occurring between October 1st and 3rd, the group said. The purchases take Brigstocke's interest in the company to 1.81m shares, or approximately 1.3% of the issued ordinary share capital. The AIM-listed technology provider DDD Group last month lowered its forecasts for 2013 in the wake of a bigger than expected decline in 3D PC market shipments and after a delay in the introduction of the next generation 3D tablets. At the same time the Los Angeles-based firm reported a loss before tax, before non-cash share based payments, of $807,000 for six months to June 2013 30th compared to a profit of $991,000 a year earlier. Revenue declined to $2.4m from $4m the previous year following the continued contraction in the PC market. Gross margin increased to 99% from 96% in June 2012.Top Director BuysNorthern 3 VCT (NTN) Director name: Mr James FergusonAmount purchased: 96,285 @ 103.86p Value: £100,002Northern Venture Trust (NVT) Director name: Mr Simon ConstantineAmount purchased: 58,353 @ 85.69p Value: £50,003Northern 2 VCT (NTV) Director name: Mr Edward Michael DennyAmount purchased: 50,255 @ 83.55p Value: £41,988Northern Venture Trust (NVT) Director name: Mr Nigel BeerAmount purchased: 46,682 @ 85.69p Value: £40,002Northern Venture Trust (NVT) Director name: Mr Timothy R LevettAmount purchased: 42,013 @ 85.69p Value: £36,001Northern 3 VCT (NTN) Director name: Mr Timothy R LevettAmount purchased: 28,885 @ 103.86p Value: £30,000Northern 3 VCT (NTN) Director name: Mr Christopher J FleetwoodAmount purchased: 19,257 @ 103.86p Value: £20,000DDD Group (DDD) Director name: Mr Nicholas O BrigstockeAmount purchased: 200,000 @ 5.69p Value: £11,380Northern 2 VCT (NTV) Director name: Mr Christopher FletcherAmount purchased: 11,968 @ 83.56p Value: £10,000Northern 2 VCT (NTV) Director name: Mr Alistair M ConnAmount purchased: 11,968 @ 83.56p Value: £10,000NR