Neil Carson, the Chief Executive Officer (CEO) of chemicals group Johnson Matthey, exercised share options and sold them immediately afterwards on the same day the company impressed the market with its full-year results.Carson, who joined the company back in 1980 and became CEO in 2004, exercised 33,407 options and disposed of the shares at a price of 2,734p each, earning him a total of £913,347.The executive share options were granted back in 2003 and had an exercise price of 898p. Carson's total holding after the transaction stood at 213,271 shares.Johnson Matthey said on Thursday that underlying profit before tax was £389.2m in the year to March 31st, down 9.0% year-on-year but ahead of the £381m consensus estimate due to a better-than-expected performance in the Environmental Technologies division.Prior to the results this week, the stock had gained nearly 9.0% since the start of 2013.