SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	9 Months Ended
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	Sep. 30, 2025
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation The interim unaudited consolidated financial statements reflect all adjustments which in the opinion of management are necessary for a fair statement of results of operations, comprehensive income, financial condition, cash flows and stockholders' equity for the periods presented. Except as otherwise disclosed, all such adjustments are of a normal recurring nature. Operating results for the interim periods are not necessarily indicative of the results that may be expected for the full year. These interim unaudited consolidated financial statements should be read in conjunction with the audited consolidated financial statements included in the Company’s 2024 Annual Report on Form 10-K. The year-end balance sheet data was derived from the audited consolidated financial statements as of December 31, 2024 but does not include all the disclosures required by accounting principles generally accepted in the United States (“GAAP”). The accounting policies of the Company are the same as those set forth in Note 2 to the audited consolidated financial statements contained in the Company’s 2024 Annual Report on Form 10-K. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Earnings Per Share The Company's unvested restricted stock units that contain non-forfeitable rights to dividends are participating securities and, therefore, are included in the earnings allocation in computing earnings per share using the two-class method. Basic earnings per common share is calculated by dividing net income attributable to Quest Diagnostics, adjusted for earnings allocated to participating securities, by the weighted average number of common shares outstanding. Diluted earnings per common share is calculated by dividing net income attributable to Quest Diagnostics, adjusted for earnings allocated to participating securities, by the weighted average number of common shares outstanding after giving effect to all potentially dilutive common shares outstanding during the period. Potentially dilutive common shares include the dilutive effect of outstanding stock options and performance share units granted under the Company's Amended and Restated Employee Long-Term Incentive Plan (“ELTIP”) and its Amended and Restated Non-Employee Director Long-Term Incentive Plan (“DLTIP”), as well as the dilutive effect of accelerated share repurchase agreements, if applicable. Earnings allocable to participating securities include the portion of dividends declared as well as the portion of undistributed earnings during the period allocable to participating securities. New Accounting Standards to be Adopted In December 2023, the Financial Accounting Standards Board ("FASB") issued a new accounting standard which will require companies to make additional income tax disclosures. The pronouncement is effective for annual filings for the year ended December 31, 2025. The Company does not expect the adoption of this standard to have a material impact on its results of operations, financial position or cash flows. In November 2024, the FASB issued a new accounting standard which will require companies to disaggregate certain income statement expenses. The pronouncement is effective for annual filings for the year ended December 31, 2027 and for interim periods within the year ended December 31, 2028. The Company does not expect the adoption of this standard to have a material impact on its results of operations, financial position or cash flows. In September 2025, the FASB issued a new accounting standard which impacts internal-use software accounting by removing all references to software development project stages such that the guidance is neutral to different software development methods. The pronouncement is effective for annual filings for the year ended December 31, 2028 and for interim periods within such year. The Company is currently evaluating the impact of the standard. In July 2025, the One Big Beautiful Bill Act (“OBBBA”) was enacted. The OBBBA makes permanent key elements of the Tax Cuts and Jobs Act of 2017, including 100% bonus depreciation, domestic research cost expensing and the business interest expense limitation, among other tax changes. Many of the tax provisions of the OBBBA are designed to accelerate tax deductions, which could lead to lower cash tax payments. The new legislation has multiple effective dates, with certain provisions effective in 2025 and others in the future. While the Company continues to assess the impact of the tax provisions of the OBBBA on its consolidated financial statements, the Company currently believes that the tax provisions of the legislation are not expected to have a material impact on the Company’s statement of operations. The Company's consolidated deferred income tax liabilities as of September 30, 2025 and December 31, 2024 were $378 million and $278 million, respectively. The increase was principally due to the domestic research cost expensing and bonus depreciation elements of the OBBBA.

QUEST DIAGNOSTICS INC 10-Q