Filed by Cigna Corporation

Pursuant to Rule 425 under the Securities Act of 1933

and deemed filed pursuant to Rule 14a-12

under the Securities Exchange Act of 1934

Subject Company: Cigna Corporation and Express Scripts Holding Company

(Commission File No. 001-08323)

Date: May 9, 2018

As part of our ongoing communications plan and support, we have updated our Q&A and created user-friendly message sheets for our more than 45,000 plus employees to use to communicate key points to their stakeholder groups regarding our pending combination with Express-Scripts.

       CIGNA & EXPRESS SCRIPTS:ACCELERATED VALUE CREATION  CIGNA ACTIVELY PURSUED A COMBINATION WITH EXPRESS SCRIPTS GIVEN ITS UNIQUE ABILITY TO DRIVE ACCELERATED GROWTH AND ENABLE INCREASED VALUE CAPTURE FOR SHAREHOLDERS  Accelerates the Strategy of Both CompaniesDeeper alignment across critical elements of the health care ecosystem positions the combined company to deliver $50 billion+ in savings  Power of AlignmentUnrivaled Predictive Capabilities: Harnesses insights to predict health and treatment adherence risksCoordinated Care and Treatment: Have reach to coordinate pharmacy, medical and behavioral health care and treatment – even for the most complex cases Aligned Incentives: Will lead the value-based and outcomes-based reward structure across the health care spectrum Enhanced ToolsInsights and Technology: Combined medical / pharmacy info for 100 million+ customers and flexible tech to share insights in an actionable wayIntegrated Model: Ability to share info seamlessly to deliver integrated care and support  Deepened Relationships: Physicians: 500+ collaborative accountable care organizationsPharmacists: Enhanced pharmacy networksDrug manufacturers: Supply chain managementDelivering ResultsLower Costs: Potential to lower medical and pharmacy cost trend to a level at or below CPI, driving $50 billion+ savings in 20211Better Quality of Care: Closes more gaps in care by getting customers the right care and treatment from the right doctor at the right timeIncreased Customer Satisfaction: More personalized care and choiceHealth Plan Clients: Will benefit from additional agnostic, portfolio of services  Delivers Differentiated Financial ResultsRobust free cash flow generation allows combined company to deleverage and deploy value-enhancing capital simultaneously  Strong EPS AccretionMID-TEENS accretion in first full year post-close2$20-$212021 EPS target increased   Substantial Cost Savings>$600 MILLIONretained synergies, primarily administrativeBILLIONSsavings for customers and clients  Balance Sheet Flexibility~$6 BILLIONfree cash flow in 2021RETURN TO 30s Projected pro forma debt-to-cap in 18-24 months post-close  Committed to retaining investment grade debt ratings  Double-digit Revenue and EPS Growth2009-2017  479% Cumulative Total Shareholder Return YE 2009-YE 2017  36% Average Annual Total Shareholder Return YE 2009-YE 2017  Cigna has a Proven Track Record of Value Creation  Less than 3% U.S. Total Medical Cost Trend*Industry leading*2017  3.6 millionCommercialMedical Customer Growth2009-2017   0.5%-1% GrowthU.S. Integrated MedicalLegacy Cigna medical offeringContracts services from the Integrated Services platform Operates as a separate verticalGrowth drivers:Cross-sells Cigna’s global offering into Express Scripts standalone PBM (10-15% client overlap)Increases penetration of pharmacy services with medical (only 50-60% of Cigna’s book is penetrated)Expands geographic reach with enhanced integrated offering Further accelerates sales of Medicare Advantage and Prescription Drug Plans   1%-2% Growth U.S. Integrated Services Combines legacy Express Scripts PBM with Cigna specialty services (e.g. PBM, wellness, behavioral)Contracts with Cigna integrated medical and third partiesOperates as a separate firewalled verticalGrowth drivers:Cross-sells other services into Express Scripts’ legacy standalone PBM businessExpands client base with the enhanced integrated offering (PBM and other services)Opens up new distribution channels for services offering through health plan clients  1. $50 billion represents annual savings opportunity for 2021 for the combined Cigna-Express Scripts membership population, assuming the combined company achieves medical/pharmacy trend equal to CPI (Consumer Price Index); 2. Excluding any contribution from Express Scripts’ transitioning clients and revenue synergies  Strengthened Growth Profile Projected Combined Company Revenue Trajectory           4%-5%  Today  B  Over the strategic horizon  6%-8%  PHARMACY SUPPLY CHAIN  PHARMACY MANAGEMENT SERVICES  HEALTH & WELLNESS SERVICES      MEDICAL INSURANCE    Financial Benefits Fact Sheet  ALIGNED HEALTH CARE PROVIDERS   A  B  A   

 FORWARD LOOKING STATEMENTSInformation included or incorporated by reference in thiscommunication, and information which may be contained inother filings with the Securities and Exchange Commission(the “SEC”) and press releases or other public statements,contains or may contain forward-looking statements. Theseforward-looking statements include, among other things,statements of plans, objectives, expectations (financial orotherwise) or intentions.Forward-looking statements, including as they relate to ExpressScripts (“Express Scripts”) or Cigna (“Cigna”), the managementof either such company or the transaction, involve risks anduncertainties. Actual results may differ significantly from thoseprojected or suggested in any forward-looking statements.Express Scripts and Cigna do not undertake any obligationto release publicly any revisions to such forward-lookingstatements to reflect events or circumstances occurring afterthe date hereof or to reflect the occurrence of unanticipatedevents. Any number of factors could cause actual results todiffer materially from those contemplated by any forward looking statements, including, but not limited to, the risksassociated with the following:the inability of Express Scripts and Cigna to obtain stockholder or regulatory approvals required for the merger or the requirement to accept conditions that could reduce the anticipated benefits of the merger as a condition to obtaining regulatory approvals;a longer time than anticipated to consummate the proposed merger;problems regarding the successful integration of the businesses of Express Scripts and Cigna;unexpected costs regarding the proposed merger;diversion of management’s attention from ongoing businessoperations and opportunities;potential litigation associated with the proposed merger;the ability to retain key personnel;the availability of financing;effects on the businesses as a result of uncertainty surrounding the proposed merger; andthe industry may be subject to future risks that are described in SEC reports filed by Express Scripts and Cigna.You should carefully consider these and other relevant factors,including those risk factors in this communication and otherrisks and uncertainties that affect the businesses of ExpressScripts and Cigna described in their respective filings with theSEC, when reviewing any forward-looking statement. Thesefactors are noted for investors as permitted under the PrivateSecurities Litigation Reform Act of 1995. Investors shouldunderstand it is impossible to predict or identify all such factorsor risks. As such, you should not consider either foregoing lists,or the risks identified in SEC filings, to be a complete discussionof all potential risks or uncertainties.IMPORTANT INFORMATION ABOUT THE TRANSACTIONAND WHERE TO FIND ITThis communication does not constitute an offer to buy orsolicitation of an offer to sell any securities. In connectionwith the proposed transaction, the newly formed companywhich will become the holding company following thetransaction (“Holdco”) intends to file with the SEC a registrationstatement on Form S-4 that will include a joint proxy statementof Cigna and Express Scripts that also constitutes a prospectusof Holdco. Cigna and Express Scripts also plan to file other relevant documents with the SEC regarding the proposedtransaction.   INVESTORS AND SECURITY HOLDERS AREURGED TO READ THE JOINT PROXY STATEMENT/PROSPECTUS AND OTHER RELEVANT DOCUMENTS FILED WITH THE SEC CAREFULLY AND IN THEIR ENTIRETY IF AND WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION. You may obtain a free copy of the joint proxy statement/prospectus (if and when it becomes available) and other relevant documents filed by Holdco, Cigna and Express Scripts with the SEC at the SEC’s website at www.sec.gov. Copies of documents filed with the SEC by Cigna will be available free of charge on Cigna’s website at www.Cigna.com or by contacting Cigna’s Investor Relations Department at (215) 761-4198. Copies of documents filed with the SEC by Express Scripts will be available free of charge on Express Scripts’ website at www.express-scripts.com or by contacting Express Scripts’ Investor Relations Department at (314) 810-3115.PARTICIPANTS IN THE SOLICITATIONCigna (and, in some instances, Holdco) and Express Scriptsand their respective directors and executive officers may bedeemed to be participants in the solicitation of proxies inrespect of the proposed transaction under the rules of theSEC. Investors may obtain information regarding the names,affiliations and interests of directors and executive officers ofCigna (and, in some instances, Holdco) in Cigna’s Annual Report on Form 10-K for the year ended December 31, 2017, which was filed with the SEC on February 28, 2018, and its definitive proxy statement for its 2018 Annual Meeting, which was filed with the SEC on March 16, 2018. Investors may obtain information regarding the names, affiliations and interests of Express Scripts’ directors and executive officers in Express Scripts’ Annual Report on Form 10-K for the year ended December 31, 2017, which was filed with the SEC on February 27, 2018, and its proxy statement for its 2018 Annual Meeting, which was filed with the SEC on March 29, 2018. You may obtain free copies of these documents at the SEC’s website at www.sec.gov, at Cigna’s website at www.Cigna.com or by contacting Cigna’s Investor Relations Department at (215) 761-4198. Copies of documents filed with the SEC by Express Scripts will be available free of charge on Express Scripts’ website at www.express-scripts.com or by contacting Express Scripts’ Investor Relations Department at (314) 810-3115. Other information regarding the participants in the proxy solicitation and a description of their direct and indirect interests, by security holdings or otherwise, will be contained in the joint proxy statement/prospectus and other relevant materials to be filed with the SEC regarding the proposed transaction if and when they become available. Investors should read the joint proxy statement/prospectus carefully and in its entirety when it becomes available before making any voting or investment decisions.NO OFFER OR SOLICITATIONThis communication is for informational purposes only and notintended to and does not constitute an offer to subscribe for,buy or sell, the solicitation of an offer to subscribe for, buy orsell or an invitation to subscribe for, buy or sell any securitiesor the solicitation of any vote or approval in any jurisdictionpursuant to or in connection with the proposed transactionor otherwise, nor shall there be any sale, issuance or transferof securities in any jurisdiction in contravention of applicablelaw. No offer of securities shall be made except by means ofa prospectus meeting the requirements of Section 10 of theSecurities Act of 1933, as amended, and otherwise in accordance with applicable law.