CLEAN HARBORS INC

The domestic and foreign components of income before provision for income taxes were as follows (in thousands):

The provision for income taxes consisted of the following (in thousands, except percentages):

The Company's effective income tax rate varied from the amount computed using the statutory federal income tax rate of 21% as follows (in thousands):

In 2024, $4.1 million in fully reserved for foreign tax credits expired. In the table above, the expiration is included in the tax credits line and the write off of the valuation allowance is contributing to the valuation allowance benefit, however the foreign tax credit expiration and associated valuation allowance write-off had no net impact to the provision for income tax. The remaining valuation allowance benefit in 2024 is the result of profitable earnings at certain Canadian entities which utilized previously reserved for operating losses.

The valuation allowance benefits recognized in 2023 are predominately the result of cumulative profitable earnings at certain US entities with historical state operating losses. As of December 31, 2023, management determined that there is sufficient positive evidence to conclude that it is more likely than not that additional deferred taxes associated with these State net operating losses are realizable. Therefore the valuation allowance was reduced accordingly.

The valuation allowance benefits recognized in 2022 were the result of cumulative profitable earnings at certain Canadian entities with historic operating losses. The 2022 earnings were sufficient to utilize substantially all of the net operating losses, and as of December 31, 2022, the Company released any remaining valuation allowances associated with these entities, which were nominal.

The components of the total net deferred tax assets and liabilities as of December 31, 2024 and 2023 were as follows (in thousands):

(1)As of December 31, 2024, the net operating loss carryforwards included (i) gross state net operating loss carryforwards of $290.7 million which will begin to expire in 2025, (ii) gross federal net operating loss carryforwards of $79.3 million which will begin to expire in 2025 and (iii) gross foreign net operating loss carryforwards of $64.3 million which will begin to expire in 2025. The increase in the state and federal net operating loss carryforward from the prior year is predominately due to assets acquired in the HEPACO transaction. See Note 4, "Business Combinations" for more information on the related transaction.

(2)Deferred tax asset acquired in the HEPACO transaction. See Note 4, "Business Combinations" for more information on the related transaction.

The Company previously recognized the U.S. federal income taxes related to the operations in Canada and has not accrued for any remaining undistributed foreign earnings. These amounts continue to be indefinitely reinvested. The amount of tax associated with those unrepatriated earnings is not expected to be material.

A valuation allowance is required to be established when, based on an evaluation of available evidence, it is more likely than not that some portion or all of the deferred tax assets will not be realized. The components of the total valuation allowance as of December 31, 2024 and 2023 were as follows (in thousands):

The Company files U.S. federal income tax returns as well as income tax returns in various states and foreign jurisdictions. The Company may be subject to examination by the Internal Revenue Service for calendar years 2018 through 2022. The Company may be subject to examination by Canadian federal and provincial authorities for calendar years 2016 through 2022 and by state and local revenue authorities for calendar years 2017 through 2022. The Company has ongoing U.S., state and local jurisdictional audits, as well as Canadian federal and provincial audits, all of which the Company believes will not result in material liabilities. The Company has not identified any material uncertain tax positions in the periods presented.

(14)EARNINGS PER SHARE

The computation of basic earnings per share (EPS) is based on the weighted-average number of our common shares outstanding. The computation of diluted EPS is based on the weighted-average number of our common shares outstanding and potential dilutive common shares during the period as determined by using the treasury stock method.

The following are computations of basic and diluted earnings per share (in thousands, except for per share amounts):

In the table above, potentially dilutive shares outstanding include the dilutive effect of unvested restricted stock awards. Shares under the Employee Stock Purchase Plan (“ESPP”) which commenced in 2024 were issued on the last day of the year and therefore are included in the weighted-average shares outstanding when issued.

Potentially dilutive shares whose effect would have been antidilutive have been excluded from the computation of diluted earnings per share. The Company included all outstanding performance awards and restricted stock awards in the calculation of diluted earnings per share except as shown in the table below (in thousands):