Calix, Inc

Filing receipts

“Research and Development Expenses The following table sets forth our research and development expenses (dollars in thousands): Three Months Ended March 28, 2026 March 29, 2025 Variance in Dollars Variance in Percent Research and development expenses $ 54,646 $ 43,980 $ 10,666 24 % Percent of revenue 20 % 20 % Percentage of gross profit 34 % 36 % Research and development expenses for the three months ended March 28, 2026 increased by $10.7 million as compared with the corresponding period in 2025 mainly due to increases in personnel expenses of $5.1 million, outside services of $3.7 million, stock-based compensation expense of $0.8 million, depreciation and amortization of $0.8 million and a...”

“General and Administrative Expenses The following table sets forth our general and administrative expenses (dollars in thousands): Three Months Ended March 28, 2026 March 29, 2025 Variance in Dollars Variance in Percent General and administrative expenses $ 28,448 $ 26,750 $ 1,698 6 % Percent of revenue 10 % 12 % General and administrative expenses for the three months ended March 28, 2026 increased by $1.7 million as compared with the corresponding period in 2025 mainly due to increases in personnel expenses of $1.0 million, mostly related to incentive compensation and increased headcount.”

“Income Taxes The following table sets forth our income taxes (dollars in thousands): Three Months Ended March 28, 2026 March 29, 2025 Variance in Dollars Variance in Percent Income taxes $ 4,022 $ 1,797 $ 2,225 124 % Effective tax rate 26.4 % (60.1) % For the three months ended March 28, 2026, our income tax expense was $4.0 million for an effective tax rate of 26.4%, which differed from the statutory rate of 21% primarily due to state taxes, the effect of non-deductible stock-based compensation for executive officers offset by the favorable impact of U.S. federal research tax credits and excess tax benefits from stock-based compensation.”