Teradyne shares fell 8.77% to $404.29 in the prior trading session. The company ranked as one of the S&P 500's largest decliners on August 19.
CEO Gregory Stephen Smith sold 4,000 shares for $1.7 million on August 17. This transaction followed a pre-arranged trading plan. Broader market caution further pressured investor sentiment during the period.
The stock maintains a year-to-date increase of over 108%.