Stock-Based Compensation

6 Months Ended

Dec. 31, 2023

Share-Based Payment Arrangement [Abstract]

Overview of Employee Stock-Based Compensation Plans

The Company currently has one equity-based compensation plan, the 2023 Long-Term Incentive Compensation Plan (the 2023 LTIP), from which stock-based compensation awards can be granted to employees and directors. In October 2023, the 2023 LTIP replaced the Company's previous equity-based compensation plan, the 2013 Long-Term Incentive Compensation Plan (the 2013 LTIP, and together with the 2023 LTIP, the LTIPs). The LTIPs provide awards in the form of incentive stock options, non-qualified stock options, stock appreciation rights, restricted stock, restricted stock units, performance shares, performance units and other awards.

The Company also has an Employee Stock Purchase Plan (ESPP) that provides employees with the opportunity to purchase common stock at a discount. The ESPP limits employee contributions to 15% of each employee’s compensation (as defined in the ESPP) and allows employees to purchase shares at a 15% discount, subject to IRS limitations. The ESPP provides for a twelve-month participation period, divided into two equal six-month purchase periods, and also provides for a look-back feature. At the end of each six-month period in April and October, participants may purchase the Company’s common stock through the ESPP at a 15% discount to the fair market value of the common stock on the first day of the twelve-month participation period or the purchase date, whichever is lower. The ESPP also provides for an automatic reset feature to start participants on a new twelve-month participation period if the fair market value of common stock declines during the first six-month purchase period.

Restricted Stock Units

A summary of nonvested restricted stock unit awards (RSUs) outstanding as of December 31, 2023 and changes during the six months then ended is as follows:


(unit awards in thousands)	Number of RSUs	Weighted Average Grant-Date Fair Value
Nonvested at June 25, 2023	2,340	$85.32
Granted	1,950	$64.26
Vested	(906)	$78.06
Forfeited	(363)	$79.78
Nonvested at December 31, 2023	3,021	$74.56

Stock-Based Compensation Valuation and Expense

The Company accounts for its employee stock-based compensation plans using the fair value method. The fair value method requires the Company to estimate the grant-date fair value of its stock-based awards and amortize this fair value to compensation expense over the requisite service period or vesting term.

The Company uses the Black-Scholes option-pricing model to estimate the fair value of the Company’s ESPP awards. The determination of the fair value of stock-based payment awards on the date of grant using an option-pricing model is affected by the Company’s stock price as well as assumptions regarding a number of complex and subjective variables. These variables include the expected stock price volatility over the term of the awards, the risk-free interest rate and expected dividends. Due to the inherent limitations of option-valuation models, future events that are unpredictable and the estimation process utilized in determining the valuation of the stock-based awards, the ultimate value realized by award holders may vary significantly from the amounts expensed in the Company’s financial statements.

For service-based RSUs and performance-based RSUs with internal metrics, the grant-date fair value is based upon the market price of the Company’s common stock on the date of the grant. For performance-based RSUs, the Company reassesses the probability of the achievement of the performance condition at each reporting period and adjusts the compensation expense for subsequent changes in the estimate or actual outcome. This fair value is then amortized to compensation expense over the requisite service period or vesting term.

For performance-based awards with market conditions, the Company estimates the grant date fair value using the Monte Carlo valuation model and expenses the awards over the vesting period regardless of whether the market condition is ultimately satisfied.

Stock-based compensation expense is recognized net of estimated forfeitures such that expense is recognized only for those stock-based awards that are expected to vest. A forfeiture rate is estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from initial estimates.

The Black-Scholes and Monte Carlo option pricing models require the input of highly subjective assumptions. These assumptions represent management's best estimates, but these estimates involve inherent uncertainties and the application of management judgment. As a result, if other assumptions had been used, recorded share-based compensation expense could have been materially different from that depicted below.

Total stock-based compensation expense was classified in the consolidated statements of operations as follows:


	Three months ended		Six months ended
(in millions of U.S. Dollars)	December 31, 2023	December 25, 2022	December 31, 2023	December 25, 2022
Cost of revenue, net	$6.4	$5.5	$12.4	$11.3
Research and development	3.4	4.1	6.1	6.5
Sales, general and administrative	12.6	9.5	23.6	21.1
Total stock-based compensation expense	$22.4	$19.1	$42.1	$38.9

Stock-based compensation expense may differ from the impact of stock-based compensation to additional paid in capital due to manufacturing related stock-based compensation capitalized within inventory.