UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, DC 20549 Form 10-Q ý Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the quarterly period ended March 31, 2023 OR ¨ Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the transition period from to Commission File Number 1-7293 TENET HEALTHCARE CORPORATION (Exact name of Registrant as specified in its charter) Nevada 95-2557091 (State of Incorporation) (IRS Employ ...