I. Stock-Based Compensation

In January 2014, Teradyne granted 0.1 million of performance-based restricted stock units (“PRSUs”) to its executive officers with a performance metric based on relative total shareholder return (“TSR”). Teradyne’s three-year TSR performance will be measured against the Philadelphia Semiconductor Index, which consists of thirty companies in the semiconductor device and capital equipment industries. The final number of TSR PRSUs that vest will vary based upon the level of performance achieved from 200% of the target shares to 0% of the target shares. All TSR PRSUs will vest upon the three-year anniversary of the January 24, 2014 grant date. No TSR PRSUs will vest if the executive officer is no longer an employee at the end of the three-year period. The TSR PRSUs are valued using a Monte Carlo simulation model. The number of units expected to be earned, based upon the achievement of the TSR market condition, is factored into the grant date Monte Carlo valuation. Compensation expense is recognized on a straight-line basis over the three-year service period. Compensation expense is recognized regardless of the eventual number of units that are earned based upon the market condition, provided the executive officer remains an employee at the end of the three-year period. Compensation expense is reversed if the executive officer is not an employee at the end of the three-year service period. During the nine months ended September 28, 2014, Teradyne granted 0.1 million TSR performance-based restricted stock unit awards with an estimated grant date fair value of $22.06 per award. The fair value was estimated using the Monte Carlo simulation model with the following assumptions:


	For the Nine Months Ended
	September 28, 2014
Risk-free interest rate		0.75	%
Teradyne volatility-historical		36.1	%
Philadelphia Semiconductor Index volatility-historical		24.6	%
Dividend yield		1.25	%

Expected volatility was based on the historical volatility of Teradyne’s stock and the Philadelphia Semiconductor Index over the most recent three-year period. The risk-free interest rate was determined using the U.S. Treasury yield curve in effect at the time of grant. Dividend yield was based upon an estimated annual dividend amount of $0.24 per share divided by Teradyne’s January 24, 2014 stock price of $19.16.

During the nine months ended September 28, 2014, Teradyne granted 1.7 million of service-based restricted stock unit awards to employees at a weighted average grant date fair value of $19.09 and 0.1 million of service-based stock options to executive officers at a weighted average grant date fair value of $5.49.

During the nine months ended September 29, 2013, Teradyne granted 1.9 million of service-based restricted stock unit awards to employees at a weighted average grant date fair value of $16.60 and 0.2 million of service-based stock options to executive officers at a weighted average grant date fair value of $6.09.

Restricted stock unit awards granted to employees vest in equal annual installments over four years. Stock options vest in equal annual installments over four years, and have a term of seven years from the date of grant.

The fair value of stock options was estimated using the Black-Scholes option-pricing model with the following assumptions:


	For the Nine Months Ended
	September 28, 2014			September 29, 2013
Expected life (years)		4.0			4.0
Risk-free interest rate		1.2	%		0.6	%
Volatility-historical		38.8	%		46.8	%
Dividend yield		1.25	%		0.0	%

Teradyne determined the stock options’ expected life based upon historical exercise data for executive officers, the age of the executive officers and the terms of the stock option grant. Volatility was determined using historical volatility for a period equal to the expected life. The risk-free interest rate was determined using the U.S. Treasury yield curve in effect at the time of grant. Dividend yield was based upon an estimated annual dividend amount of $0.24 per share divided by Teradyne’s January 24, 2014 stock price of $19.16.

Effective January 31, 2014, Michael Bradley retired as Chief Executive Officer of Teradyne. Mr. Bradley will continue to serve on Teradyne’s Board of Directors. On January 22, 2014, Teradyne entered into an agreement (the “Retirement Agreement”) with Mr. Bradley. Under the Retirement Agreement, Mr. Bradley’s unvested restricted stock units and stock options granted prior to his retirement date will continue to vest in accordance with their terms through January 31, 2017; and any vested options or options that vest during that period may be exercised for the remainder of the applicable option term. In the Retirement Agreement, Mr. Bradley agreed to be bound by non-competition and non-solicitation restrictions through January 31, 2017. In January 2014, Teradyne recorded a one-time charge to stock-based compensation expense of $6.6 million related to the Retirement Agreement.