Tenaya Therapeutics, Inc. Income Taxes Disclosure

Note 9. Income Taxes

No provision for or benefit from income taxes was recorded during the years ended December 31, 2025 and 2024. The Company has established a full valuation allowance against its net deferred tax assets due to the uncertainty regarding the realization of such assets. All losses to date have been incurred in the United States. Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets

and liabilities for financial reporting purposes and the amounts used for income tax purposes, as well as operating losses and tax credit carryforwards.

Effective Tax Rate Reconciliation

Deferred Income Taxes

Beginning January 1, 2022, the Tax Cuts and Jobs Act eliminated the option to deduct research and development expenditures in the current year and requires taxpayers to capitalize such expenses pursuant to Internal Revenue Code of 1986, as amended (IRC) Section 174. The capitalized expenses are amortized over a 5-year period for domestic expenses and a 15-year period for foreign expenses. In July 2025, legislation commonly referred to as the One Big Beautiful Bill Act (“OBBBA”) was enacted, which includes provisions affecting U.S. corporate income tax laws, including changes related to the treatment of domestic research and development expenditures. Certain provisions of the OBBBA are effective for tax years beginning after December 31, 2025, while others are effective in 2025. Additionally, the OBBBA allows immediate deduction of domestic research and development expenditures under Section 174 for tax years beginning after December 31, 2024. The Company has reflected the effects of the enactment of OBBBA for the fiscal year ended December 31, 2025. The Company will continue to evaluate the impact of enacted tax law changes on future periods.

The tax benefit of net operating losses, capitalized research expenses, temporary differences and credit carryforwards are recorded as an asset to the extent that the Company assesses that realization is more likely than not. Realization of the future tax benefits is dependent on the Company’s ability to generate sufficient taxable income within the carryforward period. As a result of the Company’s recent history of operating losses, the Company believes that recognition of deferred tax assets arising from the above-mentioned future tax benefits is currently not likely to be realized and, accordingly, has provided a full valuation allowance. The valuation allowance increased by $19.8 million and $25.0 million during the years ended December 31, 2025 and 2024, respectively. The increase in valuation allowance during the year ended December 31, 2025, was primarily due to the increase in deferred tax assets from 2025 federal net operating losses.

Net Operating Loss and Tax Credit Carryforwards

Under Section 382 of the IRC, the ability to utilize net operating loss carryforwards or other tax attributes, such as research tax credits, in any taxable year may be limited if the Company has experienced an “ownership change”. This annual limitation may result in the expiration of net operating losses and credits before utilization. The Company has not completed a detailed analysis under Section 382. Based on a preliminary assessment, changes in ownership may have occurred that could result in limitations on the utilization of net operating loss carryforwards and other tax attributes. However, the extent of any such limitation has not been determined. The Company will continue to monitor ownership changes and evaluate the impact of Section 382 on its tax attributes. The Company’s ability to use its remaining net operating loss carryforwards may be further limited if the Company experiences a Section 382 ownership change as a result of future changes in its stock ownership. Any such limitation is not expected to have a material impact on the Company’s financial statements due to the full valuation allowance recorded against its deferred tax assets.

Unrecognized Tax Benefits

The entire amount of the unrecognized tax benefits would not impact the Company’s effective tax rate if recognized as the Company continues to maintain a full valuation allowance against its deferred tax assets. The Company has elected to include interest and penalties as a component of tax expense. During the years ended December 31, 2025 and 2024, the Company did not recognize accrued interest and penalties related to unrecognized tax benefits. The Company does not anticipate that the amount of existing unrecognized tax benefits will significantly increase or decrease during the next 12 months.

Cash paid for income taxes, net of refunds, was $0 for the year ended December 31, 2025.