7. Income taxes

The Company operates in several taxing jurisdictions, including U.S. federal, multiple U.S. states, Netherlands, France and Germany. The statute of limitations has expired for all tax years prior to 2020 for federal and prior to 2017 for various state tax purposes. The statute of limitations has expired for all tax years prior to 2021 for France, prior to 2020 for Germany, and prior to 2019 for Netherlands purposes. However, the net operating loss generated on the Company’s federal and state tax returns in prior years may be subject to adjustments by the federal and state tax authorities.

As of December 31, 2023, the Company had $126,771, $66,039 and $10,851 of federal, state and foreign net operating loss carryforwards, respectively. Federal net operating loss carryforwards of $118,975 have an indefinite life while the remaining federal and state net operating loss carryforwards begin to expire in 2033 and 2028, respectively, if not utilized. Foreign net operating loss carryforwards of $10,851 also have an indefinite life. As of December 31, 2023, the Company had federal and California research and development credit carryforwards of $6,576 and $4,882, respectively. The federal credit will begin to expire in 2024; the California credit has indefinite carryforward. As of December 31, 2023, the Company had a federal foreign tax credit carryforward of $774. The federal credit will begin to expire in 2027.

Utilization of the Company’s net operating loss and tax credit carryforwards may be subject to annual limitations arising from ownership change limitations provided by the Internal Revenue Code and similar state and foreign provisions. Such annual limitations could result in the expiration of the net operating loss and tax credit carryforwards before their utilization.

The Company recognizes deferred tax assets to the extent it believes these assets are more likely than not to be realized. In making such a determination, the Company considers all available positive and negative evidence, including future reversals of existing taxable temporary differences, projected future taxable income, tax-planning strategies, and results of recent operations. The amount of deferred tax assets considered realizable is subject to adjustment in future periods if estimates of future taxable income are reduced. As of December 31, 2023 and 2022, the Company determined that net deferred tax assets are not more likely than not realizable based on cumulative three-year pretax losses and recorded a full valuation allowance. The Company’s valuation allowance may increase or decrease during the next 12 months based on future operating results. The increase in valuation allowance of $18,035 is attributable to losses generated in the current year.

The Company recognizes interest and penalties on taxes, within its income tax provision on its consolidated statements of comprehensive loss.

Included in the balance of unrecognized tax benefits as of December 31, 2023, 2022 and 2021, were $2,778, $2,366 and $2,078, respectively, of tax benefits that, if recognized, would affect the effective tax rate. The Company believes that there will be no significant increases or decreases to unrecognized tax benefits within the next 12 months.