PRESS RELEASE

UnitedHealth Group Commences Exchange Offer to Acquire Surgical Care Affiliates, Inc.

February 21, 2017

UnitedHealth Group Incorporated (NYSE: UNH) today commenced an exchange offer for all of the outstanding shares of Surgical Care Affiliates, Inc. (NASDAQ: SCAI), a leading ambulatory surgery center and surgical hospital provider, pursuant to the companies’ previously announced merger agreement dated Jan. 7, 2017.

Subject to the terms and conditions of the Offer, which is being made through a wholly owned subsidiary of UnitedHealth Group, SCA stockholders who validly tender their shares in the Offer will receive, for each share of SCA common stock, cash and UnitedHealth Group common stock valued at $57.00. The companies continue to expect the merger to close in the first half of 2017.

The combination of SCA with OptumCare, the primary and urgent care delivery services business part of Optum (UnitedHealth Group’s services business), which works with more than 80 health plans, will position the combined organization as a comprehensive provider of ambulatory care services, while continuing expansion of SCA’s network of ASCs and surgical hospitals in partnership with leading health systems, medical groups and health payers. The combination builds upon the two companies’ successful ambulatory surgery center collaborations and expands OptumCare’s capabilities in outpatient surgical procedures.

The Offer is scheduled to expire at 12:01 a.m., New York City time on Tuesday, March 21, 2017, unless earlier extended or terminated. The terms and conditions of the Offer are described in the exchange offer documents, which will be mailed to SCA stockholders and have been filed with the Securities and Exchange Commission.

Upon satisfaction of the conditions to the Offer, and after the shares tendered in the Offer are accepted for payment, UnitedHealth Group and SCA intend, as soon as practicable, to effect a merger pursuant to Section 251(h) of the Delaware General Corporation Law, which does not require a vote of SCA’s stockholders, and which would result in each outstanding share of SCA common stock not tendered in the Offer (other than shares held by SCA in treasury or by SCA stockholders who have validly exercised their appraisal rights under Delaware law) being converted into the right to receive the same consideration received for each SCA share accepted in the Offer.

The Offer is subject to customary conditions, including the tender by SCA stockholders of a number of shares of SCA common stock that represents at least a majority of the outstanding shares of SCA’s common stock and certain regulatory clearances. The applicable waiting period under the Hart-Scott-Rodino Antitrust Improvements Act has expired, and accordingly this condition to the Offer has been satisfied. No approval of the stockholders of SCA is required in connection with the proposed transaction.

The board of directors of SCA has unanimously recommended that SCA stockholders accept the Offer and tender their shares of SCA common stock to UnitedHealth Group pursuant to the Offer. Affiliates of TPG Capital, owning approximately 30 percent of the common stock of SCA, have agreed to tender their shares as part of the Offer. The merger agreement calls for the acquisition of SCA’s outstanding common stock for a fixed price of $57.00 per share, to be funded between 51 percent and 80 percent with UnitedHealth Group common stock, with the final percentage to be determined at UnitedHealth Group’s option and the remainder in cash.

In connection with the Offer, UnitedHealth Group today filed a registration statement on Form S-4, which includes a prospectus/offer to exchange and certain ancillary documentation, which will be mailed to SCA stockholders, and a tender offer statement on Schedule TO with the SEC. SCA has filed a solicitation/recommendation statement on Schedule 14D-9 that will also be mailed to SCA stockholders. These documents contain important information about the Offer that should be read carefully before any decision is made with respect to the Offer.

Requests for copies of the prospectus/offer to exchange, the accompanying letter of transmittal and other exchange offer materials may be directed to D.F. King & Co., Inc., the information agent for the exchange offer, by phone toll-free at (800) 431-9645 or by email at UNH@dfking.com.

About UnitedHealth Group

UnitedHealth Group (NYSE: UNH) is a diversified health and well-being company dedicated to helping people live healthier lives and making the health system work better for everyone. UnitedHealth Group offers a broad spectrum of products and services through two distinct platforms: UnitedHealthcare, which provides health care coverage and benefits services; and Optum, which provides information and technology-enabled health services. For more information, visit UnitedHealth Group at www.unitedhealthgroup.com or follow @UnitedHealthGrp on Twitter.

About Optum

Optum is a leading information and technology-enabled health services business dedicated to helping make the health system work better for everyone. With more than 100,000 people worldwide, Optum delivers intelligent, integrated solutions that help to modernize the health system and improve overall population health. Optum is part of UnitedHealth Group (NYSE:UNH).