A large exercise of company stock options by Hobart Kalkstein, Executive Vice President at Cabot (NYSE:CBT) was disclosed in a new SEC filing on August 21, as part of an insider exercise. What Happened: Kalkstein, Executive Vice President at Cabot, made a strategic move by exercising stock options for 20,320 shares of CBT as detailed in a Form 4 filing on Wednesday with the U.S. Securities and Exchange Commission. The transaction value amounted to $1,208,430. The latest update on Thursday morning shows Cabot shares down by 0.57%, trading at $100.44. At this price, Kalkstein’s 20,320 shares are…