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INDEX TO FINANCIAL STATEMENTS

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As filed with the Securities and Exchange Commission on February 8, 2019

Registration No. 333-           

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM S-4
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

Elanco Animal Health Incorporated
(Exact name of registrant as specified in its charter)

2500 Innovation Way
Greenfield, Indiana
46140
(877) 352-6261
(Address, Including Zip Code, and Telephone Number, Including
Area Code, of Registrant's Principal Executive Offices)

Michael-Bryant Hicks, Esq.
2500 Innovation Way
Greenfield, Indiana
46140
(877) 352-6261
(Name, Address, Including Zip Code, and Telephone Number, Including Area Code, of Agent For Service)

              Approximate date of commencement of proposed sale to the public:
As promptly as practicable after the filing of this registration statement and the satisfaction or, where legally permitted, waiver of the other conditions to the commencement of the exchange offer described herein.

              If the securities being registered on this Form are being offered in connection with the formation of a holding company and there is compliance with General Instruction G, check the following box.    o

              If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    o

              If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    o

              Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company" and "emerging growth company" in Rule 12b-2 of the Exchange Act.

              If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided to Section 7(a)(2)(B) of the Securities Act.    o

              If applicable, place an X in the box to designate the appropriate rule provision relied upon in conducting this transaction:

              Exchange Act Rule 13e-4(i) (Cross-Border Issuer Tender Offer)    o

              Exchange Act Rule 14d-1(d) (Cross-Border Third-Party Tender Offer)    o

CALCULATION OF REGISTRATION FEE

(1)

Represents the maximum number of shares of common stock, no par value ("Elanco common stock"), of Elanco Animal Health Incorporated, an Indiana corporation, to be exchanged for shares of common stock, no par value ("Lilly common stock"), of Eli Lilly and Company, an Indiana corporation, as described in the prospectus filed as part of this registration statement.

(2)

This maximum aggregate offering price assumes the acquisition of up to 67,188,216 shares of Lilly common stock in exchange for up to 293,290,000 shares of Elanco common stock held by Eli Lilly and Company. This maximum aggregate offering price, estimated solely for the purpose of calculating the registration fee in accordance with Rules 457(f) and 457(c) promulgated under the Securities Act of 1933, as amended (the "Securities Act"), is based on the product of (i) $118.10, the average of the high and low sales prices of Lilly common stock on the New York Stock Exchange on February 7, 2019 and (ii) 67,188,216, the maximum number of shares of Lilly common stock to be acquired in the exchange offer (based on the indicative exchange ratio of 4.3652 shares of Elanco common stock per share of Lilly common stock in effect following the close of trading on the New York Stock Exchange on February 7, 2019, the last trading day prior to commencement of the exchange offer).

(3)

Computed in accordance with Rule 457(f) under the Securities Act to be $961,713.31, which is equal to 0.0001212 multiplied by the proposed maximum aggregate offering price of shares of Lilly common stock to be acquired of $7,934,928,309.60.

              The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act or until this Registration Statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

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The information in this prospectus may change. Eli Lilly and Company may not complete the exchange offer and the securities being registered may not be exchanged or distributed until the registration statement filed with the Securities and Exchange Commission of which this prospectus forms a part is effective. This prospectus is not an offer to sell or exchange these securities and Eli Lilly and Company is not soliciting offers to buy or exchange these securities in any jurisdiction where the exchange offer or sale is not permitted.

ELI LILLY AND COMPANY

Offer to Exchange Up to 293,290,000 Shares of Common Stock of

ELANCO ANIMAL HEALTH INCORPORATED

Which are Owned by Eli Lilly and Company for Outstanding Shares of Common Stock of

ELI LILLY AND COMPANY

           THE EXCHANGE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, AT THE END OF THE DAY ON MARCH 8, 2019, UNLESS THE EXCHANGE OFFER IS EXTENDED OR TERMINATED.

           Eli Lilly and Company, an Indiana corporation ("Lilly"), is offering to exchange (the "exchange offer") up to an aggregate of 293,290,000 shares of common stock, no par value ("Elanco common stock"), of Elanco Animal Health Incorporated, an Indiana corporation ("Elanco"), for outstanding shares of common stock of Lilly ("Lilly common stock") that are validly tendered and not validly withdrawn.

           For each $100 of Lilly common stock accepted in the exchange offer, you will receive approximately $107.53 of Elanco common stock, subject to an upper limit of 4.5262 shares of Elanco common stock per share of Lilly common stock. The exchange offer does not provide for a lower limit or minimum exchange ratio. IF THE UPPER LIMIT IS IN EFFECT, YOU WILL RECEIVE LESS THAN $107.53 OF ELANCO COMMON STOCK FOR EACH $100 OF LILLY COMMON STOCK THAT YOU TENDER, AND YOU COULD RECEIVE MUCH LESS.

           The value of the two stocks for purposes of the preceding paragraph and this exchange offer will be determined by reference to the simple arithmetic average of the daily volume-weighted average prices ("VWAPs") of Lilly common stock (the "Average Lilly Price") and Elanco common stock (the "Average Elanco Price") on the New York Stock Exchange ("NYSE") during the three consecutive trading days ending on and including the second trading day preceding the expiration date of the exchange offer (the "Averaging Dates" and this three-day period, the "Averaging Period"), which, if the exchange offer is not extended or terminated, would be March 4, 5 and 6, 2019. See "The Exchange Offer — Terms of the Exchange Offer."

           Lilly common stock and Elanco common stock are listed on the NYSE under the symbols "LLY" and "ELAN," respectively. The reported last sale prices of Lilly common stock and Elanco common stock on the NYSE on February 7, 2019 were $117.50 and $29.50 per share, respectively. The indicative exchange ratio that would have been in effect following the official close of trading on the NYSE on February 7, 2019, based on the VWAPs of Lilly common stock and Elanco common stock on February 5, 6 and 7, 2019, would have provided for 4.3652 shares of Elanco common stock to be exchanged for every share of Lilly common stock accepted.

           The final exchange ratio, including whether the upper limit on the number of shares that can be received for each share of Lilly common tendered is in effect, will be announced by 9:00 a.m., New York City time, on the trading day immediately preceding the expiration date of the exchange offer (which expiration date, if the exchange offer is not extended or terminated, would be March 8, 2019). At such time, the final exchange ratio will be available at www.lillyexchangeoffer.com and from the information agent, Georgeson LLC, at 1-800-676-0194 (toll-free for shareholders, banks and brokers) or +1-781-575-2137 (all others outside the U.S.). Throughout the exchange offer, indicative exchange ratios (calculated in the manner described in this prospectus) also will be available on that website and from the information agent.

           You should read carefully the terms and conditions of the exchange offer described in this prospectus. None of Lilly, Elanco or any of their respective directors or officers or any of the dealer managers makes any recommendation as to whether you should tender all, some or none of your shares of Lilly common stock. You must make your own decision after reading this document and consulting with your advisors.

           Lilly's obligation to exchange shares of Elanco common stock for shares of Lilly common stock is subject to the conditions listed under "The Exchange Offer — Conditions to Completion of the Exchange Offer."

           See "Risk Factors" beginning on page 30 for a discussion of factors that you should consider in connection with the exchange offer.

           Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of the securities to be exchanged under this prospectus or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

           The dealer managers for the exchange offer are:

The date of this prospectus is February 8, 2019.

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          This prospectus incorporates by reference important business and financial information about Lilly from documents filed with the Securities and Exchange Commission (the "SEC") that have not been included herein or delivered herewith. This information is available without charge at the website that the SEC maintains at http://www.sec.gov, as well as from other sources. See "Incorporation by Reference." In addition, you may ask any questions about the exchange offer or request copies of the exchange offer documents and the other information incorporated by reference in this prospectus from Lilly, without charge, upon written or oral request to the information agent, Georgeson LLC, at 1290 Avenue of the Americas, 9th Floor, New York, NY 10104 or by calling 1-800-676-0194 (toll-free for shareholders, banks and brokers) or +1-781-575-2137 (all others outside the U.S.). In order to receive timely delivery of those materials, you must make your requests no later than five business days before expiration of the exchange offer.

          Elanco intends to amend the registration statement on Form S-4 of which this prospectus forms a part following the filing of its Annual Report on Form 10-K for the fiscal year ended December 31, 2018 with the SEC, to include certain financial and other information related to the period covered by the audited financial statements to be contained therein. You are strongly encouraged to read the amended prospectus when it becomes available, prior to making any investment decision.

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          This prospectus is not an offer to sell or exchange and it is not a solicitation of an offer to buy any shares of Lilly common stock in any jurisdiction in which the offer, sale or exchange is not permitted. Non-U.S. shareholders should consult their advisors in considering whether they may participate in the exchange offer in accordance with the laws of their home countries and, if they do participate, whether there are any restrictions or limitations on transactions in Lilly common stock or Elanco common stock that may apply in their home countries. Lilly, Elanco and the dealer managers cannot provide any assurance about whether such limitations exist.

          As used in this prospectus, unless the context requires otherwise, (i) references to "Lilly" refer to Eli Lilly and Company, an Indiana corporation, and its subsidiaries other than Elanco and Elanco's subsidiaries and (ii) references to "Elanco," our "company," "we," "us" or "our" refer to Elanco Animal Health Incorporated, an Indiana corporation and its subsidiaries. Unless the context otherwise requires or unless expressly indicated, it is assumed throughout this prospectus that the exchange offer is fully subscribed and that all shares of Elanco common stock held by Lilly are distributed pursuant to the exchange offer.

          Unless otherwise indicated, information contained in this prospectus concerning Elanco's industry and the markets in which Elanco operates, including general expectations and market positions, market opportunity and market share, is based on information from third-party sources and estimates of Elanco's management. Certain statements, where indicated, are based on information published by Vetnosis Limited ("Vetnosis"), a research and consulting firm specializing in global animal health and veterinary medicine, and estimates of Elanco's management. Management estimates are derived from publicly available information, knowledge of Elanco's industry and assumptions based on such information and knowledge, which Elanco believes to be reasonable. Management estimates have not been verified by any independent source. In addition, assumptions and estimates of Elanco's and its industry's future performances are necessarily subject to a high degree of uncertainty and risk due to a variety of factors, including those described in "Risk Factors." These and other factors could cause future performance to differ materially from Elanco's assumptions and estimates. See "Cautionary Statement Concerning Forward-Looking Statements."

NOTICE TO EEA INVESTORS

          This prospectus is only addressed to and directed at persons in member states of the European Economic Area (the "EEA") who are "qualified investors" within the meaning of Article 2(1)(e) of the Prospectus Directive (the "Qualified Investors"). This prospectus must not be acted on or relied on in any member state of the EEA by persons who are not Qualified Investors. The shares of Elanco common stock are only available to, and any investment or investment activity to which this prospectus relates is only available to, Qualified Investors, and will be engaged in only with such persons.

NOTICE TO UK INVESTORS

          In the United Kingdom, this prospectus is being distributed only to, and is directed only at, Qualified Investors: (i) who have professional experience in matters relating to investments falling within Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005, as amended, (the "Order"); or (ii) who fall within Article 49(2)(a) to (d) of the Order; or (iii) to whom it may otherwise be lawfully communicated (all such persons together being referred to as "Relevant Persons"). This prospectus must not be acted on or relied on in the United Kingdom by persons who are not Relevant Persons. The shares of Elanco common stock are only available to, and any investment or investment activity to which this prospectus relates is available only to, Relevant Persons, and will be engaged in only with such persons.

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NOTICE TO DUTCH INVESTORS

          No offer of shares of Elanco common stock which are the subject of this prospectus has been, or will be made to the public in the Netherlands, except to any legal entity which is a qualified investor (gekwalificeerde belegger) as defined in Section 1:1 of the Dutch Financial Markets Supervision Act (Wet op het financieel toezicht).

NOTICE TO NORWEGIAN INVESTORS

          In Norway, shares of Elanco common stock may be offered at any time under the following exemptions under the Prospectus Directive:

          (a)     to any legal entity which is a qualified investor, as defined under the Prospectus Directive;

          (b)     to fewer than 150 natural or legal persons (other than qualified investors as defined in the Prospectus Directive), subject to obtaining the prior consent of the Joint Global Coordinators for any such offer; or

          (c)     in any other circumstances, falling within Article 3(2) of the Prospectus Directive.

NOTICE TO JAPANESE INVESTORS

          The placement of shares of Elanco common stock in Japan, if any, will be made only to the qualified institutional investors ("QIIs") and constitute a private placement under Article 2, Paragraph 4, Item (ii)(a) of the Financial Instruments and Exchange Act of Japan (Act No. 25 of 1948, as amended, the "FIEA") and are exempt from registration requirement thereunder. Accordingly, no securities registration statement under Article 4, Paragraph 1 of the FIEA has been nor will be filed with respect to the shares of Elanco common stock. The placement in Japan will be made on a condition that any purchaser in Japan shall enter into an agreement to the effect that the purchaser will not transfer the shares of Elanco common stock to any person in Japan or to, or for the benefit of, any resident of Japan, other than a QII. Except for the private placement or resale to QIIs, the shares of Elanco common stock may not be offered or sold in Japan or to, or for the benefit of, any resident of Japan or to others for re-offering or re-sale, directly or indirectly, in Japan or to, or for the benefit of, any resident of Japan or to others for offering or resale except pursuant to an exemption from the registration requirements of, or otherwise in compliance with, the FIEA and any other applicable laws, regulations and ministerial guidelines of Japan. As used in this paragraph, "resident of Japan" means any natural person having his place of domicile or residence in Japan, including any corporation or other entity organized under the laws of Japan, or having its main office in Japan.

NOTICE TO AUSTRALIAN INVESTORS

          This document does not constitute an offer to sell, or the solicitation of an offer to buy, Lilly common stock in any jurisdiction in which such offer or solicitation is unlawful.

          No prospectus or other disclosure document has been lodged, or will be lodged, with the Australian Securities and Investments Commission ("ASIC") in relation to the exchange offer. This document does not constitute a prospectus, product disclosure statement or other disclosure document under the Corporations Act 2001 (Cth) (the "Corporations Act"), and does not purport to include the information required for a prospectus, product disclosure statement or other disclosure document under the Corporations Act.

          No offer of shares is or will be made in Australia pursuant to this document, except to a person who is (i) either a "sophisticated investor" within the meaning of section 708(8) of the

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Corporations Act or a "professional investor" within the meaning of section 9 and section 708(11) of the Corporations Act; and (ii) a "wholesale client" for the purposes of section 761G(7) of the Corporations Act (and related regulations) who has complied with all relevant requirements in this respect, or another person who may be issued shares without requiring a disclosure document.

          Any shares of Elanco common stock received in the exchange offer must not be offered for sale (or transferred, assigned or otherwise alienated) in Australia for a period of 12 months after the date of exchange under the exchange offer, except in circumstances where disclosure to investors is not required under Chapter 6D of the Corporations Act or where the offer is pursuant to a disclosure document which complies with Chapter 6D of the Corporations Act. Any person acquiring shares of Elanco common stock must observe such Australian on-sale restrictions.

          This document contains general information only and does not take account of the investment objectives, financial situation or particular needs of any particular person. It does not contain any securities recommendations or financial product advice and has been prepared without reference to individual shareholders or any other person. Before making an investment decision, investors need to consider whether the information in this document is appropriate to their needs, objectives and circumstances, and, if necessary, seek expert advice on those matters.

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INCORPORATION BY REFERENCE

          The SEC allows certain information to be "incorporated by reference" into this prospectus by Lilly, which means that Lilly can disclose important information to you by referring you to another document it has separately filed with the SEC. The information incorporated by reference is deemed to be part of this prospectus, except for any information superseded by information contained directly in this prospectus. This prospectus incorporates by reference the documents set forth below that Lilly has previously filed with the SEC. These documents contain important information about Lilly, its business, financial condition and results of operations:

Lilly SEC Filings

•

Lilly Annual Report on Form 10-K for the year ended December 31, 2017;



•

The portions of the Lilly Definitive Proxy Statement filed on March 19, 2018 that are incorporated by reference in the Lilly Annual Report on Form 10-K for the year ended December 31, 2017;



•

Lilly Quarterly Reports on Form 10-Q for the quarterly periods ended March 31, 2018, June 30, 2018 and September 30, 2018; and



•

Lilly Current Reports on Form 8-K filed on January 31, 2018, May 8, 2018, May 11, 2018, September 27, 2018, October 16, 2018, December 18, 2018, January 7, 2019 and February 6, 2019 (in each case, only for those portions that have been filed rather than furnished for the report).

          All documents filed by Lilly pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), from the date of this prospectus to the date that the exchange offer is terminated or expires shall also be deemed to be incorporated into this prospectus by reference (except for any information therein which has been furnished rather than filed). Subsequent filings with the SEC will automatically modify and supersede the information in this prospectus.

          Documents incorporated by reference are available without charge, upon written or oral request to the information agent, Georgeson LLC, at 1290 Avenue of the Americas, 9th Floor, New York, NY 10104 or by calling 1-800-676-0194 (toll-free for shareholders, banks and brokers) or +1-781-575-2137 (all others outside the U.S.). In order to receive timely delivery of those materials, you must make your requests no later than five business days before expiration of the exchange offer.

Where You Can Find More Information About Lilly and Elanco

          Lilly and Elanco file annual, quarterly and current reports, proxy statements and other information with the SEC under the Exchange Act. You may access this information on the SEC's website, which contains reports, proxy statements and other information that Lilly and Elanco file electronically with the SEC. The address of that website is http://www.sec.gov. You may also consult Lilly's and Elanco's websites for more information about Lilly and Elanco, respectively. Lilly's website is www.lilly.com. Elanco's website is www.elanco.com. Information included on these websites is not incorporated by reference into this prospectus.

          Elanco has filed a registration statement on Form S-4 under the Securities Act of 1933, as amended (the "Securities Act"), of which this prospectus forms a part, to register with the SEC the shares of Elanco common stock to be exchanged in the exchange offer. Lilly will file a Tender Offer Statement on Schedule TO with the SEC with respect to the exchange offer. This prospectus constitutes Lilly's offer to exchange, in addition to being a prospectus of Elanco. This prospectus

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does not contain all of the information set forth in the registration statement, the exhibits to the registration statement or the Schedule TO, selected portions of which are omitted from this prospectus in accordance with the rules and regulations of the SEC. For further information pertaining to Lilly, Lilly common stock, Elanco and Elanco common stock, reference is made to the registration statement and its exhibits. Statements contained in this prospectus or in any document incorporated herein by reference as to the contents of any contract or other document referred to in this prospectus or other documents that are incorporated herein by reference are not necessarily complete and, in each instance, reference is made to the copy of the applicable contract or other document filed as an exhibit to the registration statement or otherwise filed with the SEC. Each such statement contained in this prospectus is qualified in its entirety by reference to the underlying documents.

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QUESTIONS AND ANSWERS ABOUT THE EXCHANGE OFFER

          Lilly has decided to offer to exchange its remaining interest in Elanco, consisting of 293,290,000 shares of Elanco common stock, which represents approximately 80.2% of the outstanding common stock of Elanco, for outstanding shares of Lilly common stock. Following the exchange offer, Elanco will be wholly independent from Lilly, except that certain agreements between Lilly and Elanco will remain in place, and one or more Lilly executives may continue to serve on the Elanco board of directors. See "Agreements Between Lilly and Elanco and Other Related Party Transactions — Relationship between Elanco and Lilly" and "Management of Elanco — Board of Directors." The following are answers to common questions about the exchange offer.

1.      Why has Lilly decided to separate Elanco from Lilly through the exchange offer?

          Lilly has decided to commence the exchange offer to complete the separation of the Elanco animal health business from Lilly's human pharmaceutical businesses in a tax-efficient manner, with the goal of enhancing shareholder value and better positioning Lilly to focus on its human pharmaceutical business.

          Lilly believes that the separation (as defined below under "The Transaction") and the exchange offer have the potential to, among other things, (a) create a fully independent company, Elanco, focused exclusively on the animal health business, which can pursue future business initiatives, including acquisitions and other capital investments, without the influence of a controlling shareholder, (b) create a widely held, publicly traded equity security linked only to the performance of the animal health business, rather than Lilly's larger human pharmaceutical business, which can be used efficiently to attract, retain and incentivize employees of the animal health business and to pursue attractive acquisition and capital raising opportunities, and (c) enhance the capital markets efficiency of Lilly common stock, which can be used in acquisitions and capital raising activities, by eliminating a non-core business which investors may not appropriately value when assessing Lilly's business operations.

2.      Why did Lilly choose an exchange offer as the way to separate Elanco from Lilly?

          Lilly believes that the exchange offer is a tax-efficient way to divest its remaining interest in Elanco. The exchange offer is expected to qualify for non-recognition of gain and loss under Sections 355 and 368(a)(1)(D) of the Internal Revenue Code of 1986, as amended (the "Code"), and thus will give Lilly's shareholders an opportunity to adjust their current Lilly investment between Lilly and Elanco in a tax-free manner for U.S. federal income tax purposes (except with respect to cash received in lieu of a fractional share).

          Lilly and Elanco also have significantly different competitive strengths and operating strategies and operate in different industries. The exchange offer is an efficient means of placing Elanco common stock with holders of Lilly common stock who wish to directly own an interest in Elanco and reducing the total number of shares of Lilly common stock outstanding.

3.      What is the main way that the relationship between Elanco and Lilly will change after the exchange offer is completed?

          Following the completion of the exchange offer, Lilly will no longer have any ownership interest in Elanco. Elanco will be able to pursue its own initiatives, regardless of whether those initiatives are consistent with Lilly's strategy, subject to certain continuing agreements with Lilly.

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4.      Will dividends be paid on Elanco common stock?

          The declaration and payment of dividends to holders of Elanco common stock is at the discretion of Elanco's board of directors in accordance with applicable law after taking into account various factors.

          Elanco currently intends to pay a quarterly cash dividend to holders of Elanco common stock of approximately $0.06 per share commencing following the completion of the quarter during which Lilly no longer owns shares of Elanco common stock, subject to the discretion of its board of directors. Elanco's ability to pay dividends is subject to certain limitations, and Elanco may change its dividend policy at any time. See "Risk Factors — Risks Related to Elanco Common Stock — While Elanco currently intends to pay a quarterly cash dividend to its common shareholders, it may change its dividend policy at any time."

5.      Who may participate in the exchange offer and will it be extended outside the United States?

          Any U.S. holder of Lilly common stock during the exchange offer period, which will be at least 20 business days, may participate in the exchange offer, including directors and officers of Lilly, Elanco and their respective subsidiaries. This includes shares held for the account of participants of The Lilly Employee 401(k) Plan, The Savings Plan for Lilly Affiliate Employees in Puerto Rico and The Elanco US Inc. 401(k) Plan (the "Savings Plans").

          Although Lilly may deliver this prospectus to shareholders located outside the United States, this prospectus is not an offer to sell or exchange, and it is not a solicitation of an offer to buy, any shares of Lilly common stock in any jurisdiction in which such offer, sale or exchange is not permitted. This prospectus has not been reviewed or approved by any stock exchange on which shares of Lilly common stock are listed.

          Countries outside the United States generally have their own legal requirements that govern securities offerings made to persons resident in those countries and often impose stringent requirements about the form and content of offers made to the general public. Lilly has not taken any action under those non-U.S. regulations to qualify the exchange offer outside the United States but may take steps to facilitate participation of shareholders from certain jurisdictions. Therefore, the ability of any non-U.S. person to tender Lilly common stock in the exchange offer will depend on whether there is an exemption available under the laws of such person's home country that would permit the person to participate in the exchange offer without the need for Lilly or Elanco to take any action to qualify or otherwise facilitate the exchange offer in that country or otherwise. For example, some countries exempt transactions from the rules governing public offerings if they involve persons who meet certain eligibility requirements relating to their status as sophisticated or professional investors.

          All tendering shareholders must make certain representations in the letter of transmittal, including, in the case of non-U.S. shareholders, as to the availability of an exemption under their home country laws that would allow them to participate in the exchange offer without the need for Lilly or Elanco to take any action to facilitate a public offering in that country or otherwise. Lilly will rely on those representations and, unless the exchange offer is terminated, plans to accept shares validly tendered by persons who properly complete the letter of transmittal and provide any other required documentation on a timely basis and as otherwise described herein.

          Non-U.S. shareholders should consult their advisors in considering whether they may participate in the exchange offer in accordance with the laws of their home countries and, if they do participate, whether there are any restrictions or limitations on transactions in Lilly common stock or

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Elanco common stock that may apply in their home countries. Lilly, Elanco and the dealer managers cannot provide any assurance about whether such limitations exist.

          All holders who are tendering shares allocated to their Savings Plans accounts should follow the special instructions provided to them by or on behalf of their applicable plan administrator. Such participants may direct the applicable plan trustee to tender all, some or none of the shares of Lilly common stock allocated to their Savings Plan accounts, subject to certain limitations. To allow sufficient time for the tender of shares by the trustee of the applicable Savings Plan, tendering holders must provide the tabulator for the Savings Plans with the requisite instructions by the deadline specified in the special instructions provided to them, unless the exchange offer is extended. If the exchange offer is extended, and if administratively feasible, the deadline for receipt of the holder's direction also may be extended.

6.      How many shares of Elanco common stock will I receive for my shares of Lilly common stock accepted in the exchange offer?

          Unless the upper limit discussed below is in effect, the exchange offer is designed to permit you to exchange your shares of Lilly common stock for shares of Elanco common stock so that for each $100 of your Lilly common stock accepted in the exchange offer, you will receive approximately $107.53 of Elanco common stock based on the calculated per-share values determined by reference to the simple arithmetic average of the daily volume-weighted average prices ("VWAPs") for Lilly common stock (the "Average Lilly Price") and Elanco common stock (the "Average Elanco Price") on the NYSE during the three consecutive trading days ending on and including the second trading day preceding the expiration date of the exchange offer (the "Averaging Dates," and this three-day period, the "Averaging Period"). If the exchange offer is not extended or terminated, the Averaging Dates would be March 4, 5 and 6, 2019. Any changes in the prices of Lilly common stock and Elanco common stock between the conclusion of the Averaging Period and the expiration of the exchange offer will not affect the final exchange ratio.

          Please note, however, that the number of shares you can receive is subject to an upper limit of 4.5262 shares of Elanco common stock for each share of Lilly common stock accepted in the exchange offer. If the upper limit is in effect, you will receive less than $107.53 of Elanco common stock for each $100 of Lilly common stock that you tender, based on the Average Lilly Price and Average Elanco Price, and you could receive much less. The exchange offer does not provide for a lower limit or minimum exchange ratio. In addition, because the exchange offer is subject to proration, the number of shares of Lilly common stock Lilly accepts in the exchange offer may be less than the number of shares you tender.

          Lilly will announce the final exchange ratio, including whether the upper limit on the number of shares that can be received for each share of Lilly common stock validly tendered is in effect, at www.lillyexchangeoffer.com and by press release, no later than 9:00 a.m., New York City time, on the trading day immediately preceding the expiration date of the exchange offer (which expiration date, if the exchange offer is not extended or terminated, would be March 8, 2019). If the upper limit is in effect at that time, then the final exchange ratio will be fixed at the upper limit, and you will receive 4.5262 shares of Elanco common stock for each share of Lilly common stock accepted in the exchange offer.

7.      Why is there an upper limit on the number of shares of Elanco common stock I can receive for each share of Lilly common stock that I tender?

          The number of shares you can receive is subject to an upper limit of 4.5262 shares of Elanco common stock for each share of Lilly common stock accepted in the exchange offer. If the upper limit is in effect, you will receive less than $107.53 of Elanco common stock for each $100 of

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Lilly common stock that you tender, based on the Average Lilly Price and Average Elanco Price, and you could receive much less.

          This upper limit represents a 12% discount for shares of Elanco common stock based on the closing prices of Lilly common stock and Elanco common stock on the NYSE on February 7, 2019 (the trading day immediately preceding the date of the commencement of the exchange offer). Lilly set this upper limit to ensure that any unusual or unexpected decrease in the trading price of Elanco common stock, relative to the trading price of Lilly common stock, during the exchange offer period would not result in an unduly high number of shares of Elanco common stock being exchanged for each share of Lilly common stock accepted in the exchange offer.

8.      What will happen if the upper limit is in effect?

          Lilly will announce whether the upper limit on the number of shares that can be received for each share of Lilly common stock validly tendered is in effect at www.lillyexchangeoffer.com and by press release, no later than 9:00 a.m., New York City time, on the trading day immediately preceding the expiration date of the exchange offer (which expiration date, if the exchange offer is not extended or terminated, would be March 8, 2019). If the upper limit is in effect at that time, then the final exchange ratio will be fixed at the upper limit, and you will receive 4.5262 shares of Elanco common stock for each share of Lilly common stock accepted in the exchange offer. If the upper limit is in effect, you will receive less than $107.53 of Elanco common stock for each $100 of Lilly common stock that you tender based on the Average Lilly Price and Average Elanco Price, and you could receive much less.

9.      How are the Average Lilly Price and the Average Elanco Price determined for purposes of calculating the number of shares of Elanco common stock to be received for each share of Lilly common stock accepted in the exchange offer?

          The Average Lilly Price and the Average Elanco Price for purposes of the exchange offer will equal the simple arithmetic average of the daily VWAPs of shares of Lilly common stock and Elanco common stock, respectively, on the NYSE during the Averaging Period (the three consecutive trading days ending on and including the second trading day preceding the expiration date of the exchange offer). Lilly will determine the simple arithmetic average of the VWAPs of each stock, and such determination will be final. If the exchange offer is not extended or terminated, the Averaging Period would be March 4, 5 and 6, 2019. If the upper limit is in effect, you will receive 4.5262 shares of Elanco common stock for each share of Lilly common stock accepted in the exchange offer. Any changes in the prices of Lilly common stock and Elanco common stock between the conclusion of the Averaging Period and the expiration of the exchange offer will not affect the final exchange ratio.

10.    What is the daily volume-weighted average price or "VWAP"?

          The daily VWAPs for shares of Lilly common stock or Elanco common stock, as the case may be, will be the volume-weighted average price per share of that stock on the NYSE during the period beginning at 9:30 a.m., New York City time (or such other time as is the official open of trading on the NYSE), and ending at 4:00 p.m., New York City time (or such other time as is the official close of trading on the NYSE), except that such data will only take into account adjustments made to reported trades included by 4:10 p.m., New York City time. The daily VWAP will be as reported by Bloomberg L.P. as displayed under the heading Bloomberg VWAP on the Bloomberg pages "LLY UN<Equity>AQR" with respect to Lilly common stock and "ELAN UN<Equity>AQR" with respect to Elanco common stock (or their equivalent successor pages if such pages are not available). The daily VWAPs obtained from Bloomberg L.P. may be different from other sources or

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investors' or other security holders' own calculations. Lilly will determine the simple arithmetic average of the VWAPs of each stock, and such determination will be final.

          A website will be maintained at www.lillyexchangeoffer.com that will provide the daily VWAPs of both Lilly common stock and Elanco common stock during the pendency of the exchange offer. You may also contact the information agent at its toll-free number provided on the back cover of this prospectus to obtain this information.

11.    How and when will I know the final exchange ratio?

          The final exchange ratio that determines the number of shares of Elanco common stock that you will receive for each share of Lilly common stock accepted in the exchange offer, including whether the upper limit on the number of shares that can be received for each share of Lilly common stock validly tendered is in effect, will be announced by press release by 9:00 a.m., New York City time, on the trading day immediately preceding the expiration date of the exchange offer (which expiration date, if the exchange offer is not extended or terminated, would be March 8, 2019). At such time, the final exchange ratio will also be available at www.lillyexchangeoffer.com. In addition, as described below, you may also contact the information agent to obtain the final exchange ratio (after the time the final exchange ratio becomes available) at its toll-free number provided on the back cover of this prospectus.

12.    Will indicative exchange ratios be provided during the exchange offer period?

          Yes. A website will be maintained at www.lillyexchangeoffer.com that will provide the daily VWAPs of both Lilly common stock and Elanco common stock during the pendency of the exchange offer. You may also contact the information agent at its toll-free number provided on the back cover of this prospectus to obtain this information.

          Prior to the Averaging Period, commencing on the third trading day of the exchange offer, the website will also provide indicative exchange ratios for each day that will be calculated based on the indicative calculated per-share values of Lilly common stock and Elanco common stock on each day, calculated as though that day were the last day of the Averaging Period, by 4:30 p.m., New York City time. In other words, assuming that a given day is a trading day, the indicative exchange ratio will be calculated based on the simple arithmetic average of the daily VWAPs of Lilly common stock and Elanco common stock for that day and the immediately preceding two trading days. The indicative exchange ratio will also reflect whether the upper limit would have been in effect had such day been the last day of the Averaging Period.

          During the first two days of the Averaging Period, the website will provide indicative exchange ratios that will be calculated based on the Average Lilly Price and Average Elanco Price, as calculated by Lilly based on data reported by Bloomberg L.P. The website will not provide an indicative exchange ratio on the third day of the Averaging Period. The indicative exchange ratios will be calculated as follows: (i) on the first day of the Averaging Period, the indicative exchange ratio will be calculated based on the daily VWAPs of Lilly common stock and Elanco common stock for that first day of the Averaging Period and (ii) on the second day of the Averaging Period, the indicative exchange ratio will be calculated based on the simple arithmetic average of the daily VWAPs of Lilly common stock and Elanco common stock for the first and second days of the Averaging Period. During the first two days of the Averaging Period, the indicative exchange ratios will be updated on the website each day by 4:30 p.m., New York City time. The final exchange ratio, including whether the upper limit on the number of shares that can be received for each share of Lilly common stock validly tendered is in effect, will be announced by press release and be available on the website by 9:00 a.m., New York City time, on the trading day immediately

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preceding the expiration date of the offer (which expiration date, if the exchange offer is not extended or terminated, would be March 8, 2019).

          In addition, a table indicating the number of shares of Elanco common stock that you would receive per share of Lilly common stock, calculated on the basis described above and taking into account the upper limit, assuming a range of averages of the VWAPs of Lilly common stock and Elanco common stock during the Averaging Period, is provided herein for purposes of illustration. See "The Exchange Offer — Terms of the Exchange Offer — Final Exchange Ratio."

13.    What if the trading market in either shares of Lilly common stock or Elanco common stock is disrupted on one or more days during the Averaging Period?

          If a market disruption event (as defined below under "The Exchange Offer — Terms of the Exchange Offer — Final Exchange Ratio") occurs with respect to shares of Lilly common stock or Elanco common stock on any day during the Averaging Period, the simple arithmetic average stock price of Lilly common stock and Elanco common stock will be determined using the daily VWAPs of shares of Lilly common stock and Elanco common stock on the preceding trading day or days, as the case may be, on which no market disruption event occurred. If, however, Lilly decides to extend the exchange offer period following a market disruption event, the Averaging Period will be reset. If a market disruption event occurs, Lilly may terminate the exchange offer if, in its reasonable judgment, the market disruption event has impaired the benefits of the exchange offer. See "The Exchange Offer — Conditions to Completion of the Exchange Offer."

14.    Are there circumstances under which I would receive fewer shares of Elanco common stock than I would have received if the exchange ratio were determined using the closing prices of the shares of Lilly common stock and Elanco common stock on the expiration date of the exchange offer?

          Yes. For example, if the trading price of shares of Lilly common stock were to increase during the last two trading days of the exchange offer, the Average Lilly Price would likely be lower than the closing price of shares of Lilly common stock on the expiration date of the exchange offer. As a result, you may receive fewer shares of Elanco common stock for each $100 of Lilly common stock than you would have if the Average Lilly Price were calculated on the basis of the closing price of shares of Lilly common stock on the expiration date of the exchange offer or on the basis of an Averaging Period that includes the last two trading days of the exchange offer. Similarly, if the trading price of Elanco common stock were to decrease during the last two trading days of the exchange offer, the Average Elanco Price would likely be higher than the closing price of shares of Elanco common stock on the expiration date of the exchange offer. This could also result in your receiving fewer shares of Elanco common stock for each $100 of Lilly common stock than you would otherwise receive if the Average Elanco Price were calculated on the basis of the closing price of shares of Elanco common stock on the expiration date of the exchange offer or on the basis of an Averaging Period that included the last two trading days of the exchange offer.

15.    Will I receive any fractional shares of Elanco common stock in the exchange offer?

          No. Fractional shares of Elanco common stock will not be distributed in the exchange offer. Instead, you will receive cash in lieu of a fractional share. The exchange agent, acting as agent for the Lilly shareholders otherwise entitled to receive a fractional share of Elanco common stock, will aggregate all fractional shares that would otherwise have been required to be distributed and cause them to be sold in the open market for the accounts of those shareholders. Any proceeds that the exchange agent realizes from the sale will be distributed, less any brokerage commissions or other fees, to each shareholder entitled thereto in accordance with such shareholder's proportional interest in the aggregate number of shares sold. The distribution of fractional share proceeds may

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take longer than the distribution of shares of Elanco common stock. As a result, shareholders may not receive fractional share proceeds at the same time they receive shares of Elanco common stock.

16.    Will all the shares of Lilly common stock that I tender be accepted in the exchange offer?

          Not necessarily. The maximum number of shares of Lilly common stock that will be accepted if the exchange offer is completed will be equal to the number of shares of Elanco common stock held by Lilly divided by the final exchange ratio (which will be subject to the upper limit). Lilly holds 293,290,000 shares of Elanco common stock. Accordingly, the largest possible number of shares of Lilly common stock that will be accepted equals 293,290,000 divided by the final exchange ratio. Depending on the number of shares of Lilly common stock validly tendered in the exchange offer and not validly withdrawn, and the Average Lilly Price and Average Elanco Price, Lilly may have to limit the number of shares of Lilly common stock that it accepts in the exchange offer through a proration process. Any proration of the number of shares accepted in the exchange offer will be determined on the basis of the proration mechanics described under "The Exchange Offer — Terms of the Exchange Offer — Proration; Odd-Lots."

17.    Are there any conditions to Lilly's obligation to complete the exchange offer?

          Yes. Lilly is not required to complete the exchange offer unless the conditions described under "The Exchange Offer — Conditions to Completion of the Exchange Offer" are satisfied or, where legally permitted, waived before the expiration of the exchange offer. For example, Lilly is not required to complete the exchange offer unless (i) at least 146,645,000 shares of Elanco common stock will be distributed in exchange for shares of Lilly common stock that are validly tendered in the exchange offer, and (ii) Lilly receives an opinion of counsel to the effect that the exchange offer will qualify for non-recognition of gain and loss under Sections 355 and 368(a)(1)(D) of the Code. The minimum number of shares of Lilly common stock that must be validly tendered in order for at least 146,645,000 shares of Elanco common stock to be distributed in the exchange offer is referred to as the "minimum amount." Lilly may waive any or all of the conditions to the exchange offer, subject to limited exceptions. Elanco has no right to waive any of the conditions to the exchange offer.

18.    How many shares of Lilly common stock will Lilly acquire if the exchange offer is completed?

          The number of shares of Lilly common stock that will be accepted if the exchange offer is completed will depend on the final exchange ratio and the number of shares of Lilly common stock validly tendered and not validly withdrawn. The maximum number of shares of Lilly common stock that will be accepted if the exchange offer is completed will be equal to the number of shares of Elanco common stock held by Lilly divided by the final exchange ratio (which will be subject to the upper limit). Lilly holds 293,290,000 shares of Elanco common stock. Accordingly, the largest possible number of shares of Lilly common stock that will be accepted equals 293,290,000 divided by the final exchange ratio. For example, assuming that the final exchange ratio is 4.5262 (the upper limit for shares of Elanco common stock that could be exchanged for one share of Lilly common stock), then Lilly would accept up to 64,798,286 shares of Lilly common stock.

19.    What happens if more than the minimum number of shares are validly tendered, but not enough shares of Lilly common stock are validly tendered to allow Lilly to exchange all of the shares of Elanco common stock it owns?

          In that case, following the completion of the exchange offer, Lilly will continue to hold shares of Elanco common stock not distributed in the exchange offer. Depending on the number of shares

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validly tendered, Lilly may be able to influence the outcome of certain corporate actions requiring shareholder approval so long as it owns a significant portion of Elanco common stock and may retain certain rights pursuant to the master separation agreement. See "Agreements Between Lilly and Elanco and Other Related Party Transactions — Relationship between Elanco and Lilly — Master Separation Agreement." If the exchange offer is not fully subscribed, and Lilly were to waive the minimum condition and continue to hold more than 50% of the outstanding Elanco common stock, then Elanco would continue to be considered a "controlled company" under NYSE rules. In such case, the typical independence requirements under the NYSE rules would not apply to Elanco.

          In addition, if Lilly does not exchange all of the shares of Elanco common stock it holds, Lilly intends to conduct one or more additional exchange offers and/or distribute all of its remaining shares of Elanco common stock through a special dividend to all Lilly shareholders, on a pro rata basis (a "pro rata spin-off"). In such event, Lilly and Elanco, as applicable, will file any documents required by U.S. securities laws in connection with such pro rata spin-off or exchange and will not rely on this prospectus or the registration statement of which it forms a part in connection with such distribution.

20.    What happens if the exchange offer is oversubscribed and Lilly is unable to accept all tenders of Lilly common stock at the exchange ratio?

          In that case, all shares of Lilly common stock that are validly tendered and not validly withdrawn will generally be accepted for exchange on a pro rata basis in proportion to the number of shares validly tendered, which is referred to as "proration." Shareholders who beneficially own "odd-lots" (less than 100 shares) of Lilly common stock and who validly tender all of their shares will not be subject to proration. For instance, if you beneficially own 50 shares of Lilly common stock and tender all 50 shares, your odd-lot will not be subject to proration. If, however, you hold less than 100 shares of Lilly common stock, but do not tender all of your shares, you will be subject to proration to the same extent as holders of more than 100 shares if the exchange offer is oversubscribed. Direct or beneficial holders of 100 or more shares of Lilly common stock will be subject to proration. In addition, shares held on behalf of participants in the Savings Plans (each of which holds more than 100 shares of Lilly common stock) will be subject to proration.

          Proration for each tendering shareholder will be based on the number of shares of Lilly common stock validly tendered by that shareholder in the exchange offer, and not on that shareholder's aggregate ownership of Lilly common stock. Any shares of Lilly common stock not accepted for exchange as a result of proration will be returned to tendering shareholders. Lilly will announce its preliminary determination, if any, of the extent to which tenders will be prorated by press release by 9:00 a.m., New York City time, on the business day immediately following the expiration date of the exchange offer (which expiration date, if the exchange offer is not extended or terminated, would be March 8, 2019). This preliminary determination is referred to as the "preliminary proration factor." Lilly will announce its final determination of the extent to which tenders will be prorated by press release promptly after this determination is made. This final determination is referred to as the "final proration factor."

21.    How long will the exchange offer be open?

          The period during which you are permitted to tender your shares of Lilly common stock in the exchange offer will expire at 12:00 midnight, New York City time, at the end of the day on the expiration date of the exchange offer (which, if the exchange offer is not amended or terminated, would be March 8, 2019), unless the exchange offer is extended or terminated. Lilly may extend the exchange offer in the circumstances described in "The Exchange Offer — Extension; Amendment — Extension or Amendment by Lilly."

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          All holders who are tendering shares allocated to their Savings Plans accounts should follow the special instructions provided to them by or on behalf of their applicable plan administrator.

22.    Under what circumstances can the exchange offer be extended by Lilly?

          Lilly can extend the exchange offer at any time, in its sole discretion, and regardless of whether any condition to the exchange offer has been satisfied or, where legally permitted, waived. If Lilly extends the exchange offer, it must publicly announce the extension by press release at any time prior to 9:00 a.m., New York City time, on the next business day after the previously scheduled expiration date of the exchange offer.

23.    How do I decide whether to participate in the exchange offer?

          Whether you should participate in the exchange offer depends on many factors. You should examine carefully your specific financial position, plans and needs before you decide whether to participate, as well as the relative risks associated with an investment in Elanco and Lilly.

          In addition, you should consider all of the factors described in "Risk Factors." None of Lilly, Elanco or any of their respective directors or officers or any of the dealer managers or any other person makes any recommendation as to whether you should tender all, some or none of your shares of Lilly common stock. You must make your own decision after carefully reading this prospectus, and the documents incorporated by reference, and consulting with your advisors in light of your own particular circumstances. You are strongly encouraged to read this prospectus in its entirety, including all documents referred to herein, very carefully.

24.    How do I participate in the exchange offer?

          The procedures you must follow to participate in the exchange offer will depend on whether you hold your shares of Lilly common stock in certificated form, in uncertificated form registered directly in your name in Lilly's share register ("Direct Registration Shares"), or through a broker, dealer, commercial bank, trust company, custodian or similar institution or otherwise. For specific instructions about how to participate, see "The Exchange Offer — Procedures for Tendering."

25.    Can I tender only a part of my Lilly common stock in the exchange offer?

          Yes. You may tender all, some or none of your Lilly common stock.

26.    Will holders of Lilly unvested restricted stock units ("RSUs"), performance awards or shareholder value awards have the opportunity to exchange their Lilly RSUs, performance awards or shareholder value awards for Elanco common stock in the exchange offer?

          No, holders of unvested RSUs, performance awards or shareholder value awards cannot tender the shares underlying such awards in the exchange offer. If you hold shares of Lilly common stock as a result of the vesting and settlement of RSUs, performance awards or shareholder value awards during the exchange offer period, these shares can be tendered in the exchange offer.

27.    How can I participate in the exchange offer if shares of Lilly common stock are held for my account under a Savings Plan?

          Shares of Lilly common stock held for the account of participants in the Savings Plans are eligible for participation in the exchange offer. A Savings Plan participant may direct that all, some or none of the shares of Lilly common stock allocated to his or her Savings Plan account be exchanged, subject to the Savings Plan's rules for participating in the exchange offer.

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          A Savings Plan's rules and procedures for tendering shares held by the Savings Plan for the account of participants will be different than those described in this prospectus. For example, the process for submitting instructions to tender or withdraw the tender of Savings Plan shares may be different, and the deadlines for receipt of such instructions may be earlier than the expiration date of the exchange offer (including any extensions thereof). Proceeds from the exchange offer may be provided to Savings Plan participants in the form of units of the Saving Plan's Elanco Stock Fund that contain a cash component. Such units may be credited later than described in this prospectus and may not be subject to the treatment of fractional shares as described in this prospectus. With respect to The Lilly Employee 401(k) Plan and The Savings Plan for Lilly Affiliate Employees in Puerto Rico, shares of Elanco common stock will only be held for a limited duration (i.e., until on or about December 11, 2019), after which time investments in the saving plan's Elanco Stock Fund will be liquidated and reinvested in the investment fund designated as such savings plan's qualified default investment alternative (i.e., the appropriate target date portfolio based on the year you turn age 60). With respect to The Elanco US Inc. 401(k) Plan, whether or not a participant in such savings plan elects to participate in the exchange offer, shares of both Lilly common stock and Elanco common stock will be held for a limited duration (i.e., until on or about December 11, 2019), after which time investments in both the saving plan's Lilly Stock Fund and Elanco Stock Fund will be liquidated and reinvested in the investment fund designated as such saving plan's qualified default investment alternative. Savings Plan participants may face different risks than other participants in the exchange offer due to these different rules.

          The Savings Plans' rules are described in a separate notice, which will be made available to the Savings Plan participants. Savings Plan participants should consult this additional notice together with this prospectus in deciding whether or not to participate in the exchange offer with respect to their Savings Plan shares.

28.    What do I do if I want to retain all of my Lilly common stock?

          If you want to retain your Lilly common stock, you do not need to take any action in connection with the exchange offer.

29.    Will I be able to withdraw the shares of Lilly common stock that I tender in the exchange offer?

          Yes. You may withdraw shares tendered at any time before the exchange offer expires. See "The Exchange Offer — Withdrawal Rights." If you change your mind again before the expiration of the exchange offer, you can re-tender your Lilly common stock by following the tender procedures again.

30.    Will I be able to withdraw the shares of Lilly common stock that I tender in the exchange offer before and after the final exchange ratio has been determined?

          Yes. The final exchange ratio used to determine the number of shares of Elanco common stock that you will receive for each share of Lilly common stock accepted in the exchange offer, including whether the upper limit is in effect, will be announced by 9:00 a.m., New York City time, on the trading day immediately preceding the expiration date of the exchange offer (which expiration date, if the exchange offer is not extended or terminated, would be March 8, 2019). The expiration date of the exchange offer may be extended or the exchange offer may be terminated. You have a right to withdraw shares of Lilly common stock you have tendered for two trading days after the final exchange ratio has been established. If you change your mind again before the expiration of the exchange offer, you can re-tender shares of Lilly common stock by following the exchange procedures again prior to the expiration of the exchange offer. See "The Exchange Offer — Withdrawal Rights."

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          If you are a registered holder of Lilly common stock (which includes persons holding certificated shares and Direct Registration Shares), you must provide a written notice of withdrawal or email transmission notice of withdrawal to the exchange agent before 12:00 midnight, New York City time, at the end of the day on the expiration date of the exchange offer (which, if the exchange offer is not extended or terminated, would be March 8, 2019). The information that must be included in that notice is specified under "The Exchange Offer — Withdrawal Rights."

          If you hold your shares through a broker, dealer, commercial bank, trust company, custodian or similar institution, you should consult with that institution on the procedures with which you must comply and the time by which such procedures must be completed in order for that institution to provide a written notice of withdrawal or email transmission notice of withdrawal to the exchange agent on your behalf before 12:00 midnight, New York City time, at the end of the day on the expiration date of the exchange offer (which, if the exchange offer is not extended or terminated, would be March 8, 2019). If you hold your shares through such an institution, that institution must deliver the notice of withdrawal with respect to any shares you wish to withdraw. In such a case, as a beneficial owner and not a registered shareholder, you will not be able to provide a notice of withdrawal for such shares directly to the exchange agent. The Depository Trust Company ("DTC") is expected to remain open until 5:00 p.m., New York City time, and institutions may be able to process withdrawals through DTC until that time (although there is no assurance that will be the case). Once DTC has closed, if you beneficially own shares that were previously delivered through DTC, then in order to withdraw your shares the institution through which your shares are held must deliver a written notice of withdrawal or email transmission notice of withdrawal to the exchange agent prior to 12:00 midnight, New York City time, at the end of the day on the expiration date of the exchange offer (which, if the exchange offer is not extended or terminated, would be March 8, 2019). Such notice of withdrawal must be in the form of DTC's notice of withdrawal. Shares can be withdrawn only if the exchange agent receives a withdrawal notice directly from the relevant institution that tendered the shares through DTC. On the last day of the exchange offer, beneficial owners who cannot contact the institution through which they hold their shares will not be able to withdraw their shares.

          If you hold your shares through the Savings Plans, you will be provided with special instructions by or on behalf of your plan administrator on how to withdraw your shares and you must deliver any required information in a timely manner in order for the tabulator for the Savings Plans to withdraw your election to exchange from the final tabulation. The deadline will be specified in the special instructions provided to you (or, if the exchange offer is extended, on the new plan participant withdrawal deadline).

31.    How soon will I receive delivery of my Elanco common stock once I have validly tendered my Lilly common stock?

          Assuming the shares of Lilly common stock validly tendered in the exchange offer have been accepted for exchange, the exchange agent will cause shares of Elanco common stock to be credited in book-entry form to direct registered accounts maintained by Elanco's transfer agent for your benefit (or, in the case of shares tendered through DTC, to the account of DTC so that DTC can credit the relevant DTC participant and such participant can credit you) promptly after the expiration of the exchange offer. See "The Exchange Offer — Delivery of Elanco Common Stock; Book-Entry Accounts."

32.    Will I be taxed on the shares of Elanco common stock that I receive in the exchange offer?

          The exchange offer is conditioned upon the receipt by Lilly of an opinion of Skadden, Arps, Slate, Meagher & Flom LLP ("Skadden Arps"), to the effect that the exchange offer will qualify as a

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tax-free transaction under Sections 355 and 368(a)(1)(D) of the Code and that, for U.S. federal income tax purposes, except with respect to the receipt of cash in lieu of fractional shares, holders of Lilly common stock will recognize no gain or loss upon the receipt of shares of Elanco common stock in the exchange offer. A holder of Lilly common stock will generally recognize capital gain or loss with respect to cash received in lieu of a fractional share of Elanco common stock.

          Please see "Risk Factors — Risks Related to the Exchange Offer — The exchange offer could result in significant tax liability," "Risk Factors — Risks Related to Elanco Common Stock — If there is a later determination that the exchange offer is taxable for U.S. federal income tax purposes because the facts, assumptions, representations or undertakings underlying the tax opinion are incorrect or for any other reason, then Lilly and its shareholders could incur significant U.S. federal income tax liabilities, and Elanco could incur significant liabilities" and "Material U.S. Federal Income Tax Consequences" for more information regarding the tax opinion and the potential tax consequences of the exchange offer. Holders of Lilly common stock should consult their tax advisor as to the particular tax consequences to them of the exchange offer.

33.    Are there any appraisal rights for holders of Lilly or Elanco common stock?

          There are no appraisal rights available to Lilly shareholders or Elanco shareholders in connection with the exchange offer.

34.    What is the accounting treatment of the exchange offer?

          The shares of Lilly common stock acquired by Lilly in the exchange offer will be recorded as an acquisition of treasury stock at a cost equal to the market value of the shares of Lilly common stock accepted in the exchange offer at its expiration. Any difference between the net book value of Elanco attributable to Lilly and the market value of the shares of Lilly common stock acquired at that date will be recognized by Lilly as a gain on disposal of discontinued operations net of any direct and incremental expenses of the exchange offer on the disposal of its Elanco common stock.

          Also, upon completion of the exchange offer, Elanco's historical results will be shown in Lilly's financial statements as discontinued operations, and, in subsequent periods, Lilly's financial statements will no longer reflect the assets, liabilities, results of operations or cash flows attributable to Elanco.

35.    What will Lilly do with the shares of Lilly common stock it acquires in the exchange offer?

          Lilly common stock acquired by Lilly in the exchange offer will be held as treasury stock unless and until retired or used for other purposes.

36.    What is the impact of the exchange offer on the number of Lilly shares outstanding?

          Any Lilly common stock acquired by Lilly in the exchange offer will reduce the total number of Lilly shares outstanding, although Lilly's actual number of shares outstanding on a given date reflects a variety of factors, such as the vesting and settlement of RSUs, performance awards or shareholder value awards.

37.    Do the statements on the cover page regarding this prospectus being subject to change and the registration statement filed with the SEC not yet being effective mean that the exchange offer has not commenced?

          As permitted under SEC rules, Lilly has commenced the exchange offer without the registration statement, of which this prospectus forms a part, having been declared effective by the SEC. Lilly cannot, however, complete the exchange offer and accept for exchange any shares of

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Lilly common stock validly tendered and not validly withdrawn in the exchange offer until the registration statement is effective and the other conditions to the exchange offer have been satisfied or, where legally permitted, waived.

          Elanco intends to amend the registration statement, of which this prospectus forms a part, following the filing of its Annual Report on Form 10-K for the fiscal year ended December 31, 2018 with the SEC, to include certain financial and other information related to the period covered by the audited financial statements to be contained therein. You are strongly encouraged to read the amended prospectus when it becomes available, prior to making any investment decision.

38.    Where can I find out more information about Lilly and Elanco?

          You can find out more information about Lilly and Elanco by reading this prospectus and, with respect to Lilly, from various sources described in "Incorporation by Reference."

39.    Whom should I call if I have questions about the exchange offer or want copies of additional documents?

          You may ask any questions about the exchange offer or request copies of the exchange offer documents and the other information incorporated by reference in this prospectus, without charge, from the information agent, Georgeson LLC, at 1290 Avenue of the Americas, 9th Floor, New York, NY 10104 or by calling 1-800-676-0194 (toll-free for shareholders, banks and brokers) or +1-781-575-2137 (all others outside the U.S.).

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