YOUR VOTE IS IMPORTANT

You mayYour vote is very important. To ensure your ordinary shares by using a toll-free telephone numberrepresentation at the special meeting, please complete and return the enclosed proxy card or electronically over the Internet as described on the proxy form. We encourage you to filesubmit your proxy using either of these options if they are available to you. Alternatively, you may mark, sign, date and mailby telephone or through the Internet.Please submit your proxy form inpromptly whether or not you expect to attend the postage-paid envelope provided. The method by whichspecial meeting. Submitting a proxy now will not prevent you vote does not limit your rightfrom being able to vote in person at the Actavis EGM. We strongly encouragespecial meeting.

The KYTHERA board of directors has unanimously approved and declared advisable the Merger Agreement and unanimously recommends that you to vote.

Notes:vote “FOR” the Merger Proposal, “FOR” the Adjournment Proposal and “FOR” the Merger-Related Named Executive Officer Compensation Proposal.

Please note that if shareholders plan to attend the Actavis EGM in person, they will need to register in advance to be admitted. Holders of record can register for the Actavis EGM by checking the appropriate box on their proxy card. The Actavis EGM will start promptly at [—] (local time).Westlake Village, California

In addition to registering in advance, shareholders will be required to present a valid government-issued photo identification (e.g., driver’s license or passport) to enter the Actavis EGM. Holders of record, whose ordinary shares are registered in their name, should bring a valid form of photo identification to the Actavis EGM. Beneficial holders whose ordinary shares are held in “street name” will need to bring a letter from their bank, broker or other nominee that confirms that such holder is the beneficial owner of such ordinary shares as of the record date, together with a valid form of photo identification. Beneficial holders whose ordinary shares are held in “street name” and who plan to vote at the Actavis EGM must also obtain a legal proxy, executed in their favor by or on behalf of their bank, broker or other nominee, to be able to vote at the Actavis EGM. Actavis reserves the right to deny admittance to anyone who cannot adequately show proof of share ownership as of [—●], 2015. See “The Actavis Extraordinary General Meeting” beginning on page [—] of the accompanying joint proxy statement/prospectus.2015

PLEASE SUBMIT A PROXY FOR YOUR SHARES OF KYTHERA COMMON STOCK PROMPTLY. YOU CAN FIND INSTRUCTIONS FOR DOING SO ON THE ENCLOSED PROXY CARD. IF YOU HAVE QUESTIONS ABOUT THE PROPOSALS OR ABOUT VOTING YOUR SHARES, PLEASE CALL (800) 322-2885 (TOLL-FREE) OR (212) 929-5500 (COLLECT).

ALLERGAN, INC.

2525 DUPONT DRIVE

IRVINE, CA 92612

NOTICE OF A SPECIAL MEETING OF STOCKHOLDERS

TO BE HELD ON [—●], 2015

NOTICE IS HEREBY GIVEN that a special meeting (the “special meeting”) of the stockholders of Allergan,KYTHERA Biopharmaceuticals, Inc. (“Allergan”KYTHERA”) will be held at [—[●] at [—[●] (local time) on [—[●], 2015 for the following purposes:

1. to adopt the Agreement and Plan of Merger, dated as of November 16, 2014, as it may be amended from time to time (the “Merger Agreement”), by and among Actavis plc, Avocado Acquisition Inc. (“Merger Sub”) and Allergan (the “Merger Proposal”);

2. to approve the adjournment of the meeting to another date and place if necessary or appropriate to solicit additional votes in favor of the Merger Proposal (the “Allergan Adjournment Proposal”); and

3. to approve, on a non-binding, advisory basis, the compensation to be paid to Allergan’s named executive officers that is based on or otherwise relates to the Merger (the “Merger-Related Named Executive Officer Compensation Proposal”), as disclosed pursuant to Item 402(t) of Regulation S-K in “The Merger—Interests of Allergan’s Directors and Executive Officers in the Transaction—Quantification of Payments and Benefits to Allergan’s Named Executive Officers” beginning on page [—] of the accompanying joint proxy statement/prospectus.

The approval by AllerganKYTHERA stockholders of the Merger Proposal is required to complete the Mergermerger (the “Merger”) described in the accompanying joint proxy statement/prospectus.

AllerganKYTHERA will transact no other business at the special meeting, except for business properly brought before the special meeting or any adjournment or postponement thereof.

The Merger Proposal is described in more detail in the accompanying joint proxy statement/prospectus, which you should read carefully in its entirety before you vote. A copy of the Merger Agreement is attached as Annex A to this document.the accompanying proxy statement/prospectus.

The AllerganKYTHERA board of directors has set [—[●], 2015 as the record date for the Allergan special meeting. Only holders of record of shares of AllerganKYTHERA common stock at the close of business on [—[●], 2015 will be entitled to notice of and to vote at the Allergan special meeting and any adjournments thereof. Any stockholder entitled to attend and vote at the Allergan special meeting is entitled to appoint a proxy to attend and vote on such stockholder’s behalf. Such proxy need not be a holder of shares of AllerganKYTHERA common stock.

Your vote is very important. To ensure your representation at the Allergan special meeting, please complete and return the enclosed proxy card or submit your proxy by telephone or through the Internet.Please submit your proxy promptly whether or not you expect to attend the Allergan special meeting. Submitting a proxy now will not prevent you from being able to vote in person at the Allergan special meeting.

The AllerganKYTHERA board of directors has unanimously approved and declared advisable the Merger Agreement and unanimously recommends that you vote “FOR” the Merger Proposal, “FOR” the Allergan Adjournment Proposal and “FOR” the Merger-Related Named Executive Officer Compensation Proposal.

BY ORDER OF THE BOARD OF DIRECTORS

Matthew J. Maletta

Vice President,

Associate General Counsel and Secretary

Irvine,Westlake Village, California

[—●], 2015

PLEASE SUBMIT A PROXY FOR YOUR SHARES OF ALLERGANKYTHERA COMMON STOCK PROMPTLY. YOU CAN FIND INSTRUCTIONS FOR DOING SO ON THE ENCLOSED PROXY CARD. IF YOU HAVE QUESTIONS ABOUT THE PROPOSALS OR ABOUT VOTING YOUR SHARES, PLEASE CALL 877-800-5187(800) 322-2885 (TOLL-FREE) OR 212-750-5833(212) 929-5500 (COLLECT).

ADDITIONAL INFORMATION

The accompanying proxy statement/prospectus incorporates by reference important business and financial information about Allergan and KYTHERA from documents that are not included in or delivered with the accompanying proxy statement/prospectus. This information is available without charge to you upon written or oral request. You can obtain the documents incorporated by reference in the proxy statement/prospectus by requesting them in writing, by email or by telephone from Allergan or KYTHERA at their respective addresses and telephone numbers listed below or by accessing the websites listed below. The information provided on the websites listed below is not a part of the accompanying proxy statement/prospectus and therefore is not incorporated by reference into the accompanying proxy statement/prospectus.

In addition, if you have questions about the Merger or the KYTHERA special meeting, or if you need to obtain copies of the accompanying proxy statement/prospectus, proxy card or other documents incorporated by reference in the accompanying proxy statement/prospectus, you may contact the KYTHERA proxy solicitation agent at the address and telephone number listed below. You will not be charged for any of the documents you request.

MacKenzie Partners Inc.

105 Madison Avenue

New York, NY 10016

Telephone: (212) 929-5500 (call collect)

or

Toll-Free (800) 322-2885

To obtain timely delivery of these documents before the KYTHERA special meeting, you must request the

information no later than [●], 2015.

For a more detailed description of the information incorporated by reference in the accompanying proxy statement/prospectus and how you may obtain it, see the section entitled “Where You Can Find More Information” beginning on page [●] of the accompanying proxy statement/prospectus.

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QUESTIONS AND ANSWERS ABOUT THE TRANSACTIONSMERGER AND THE ACTAVIS EXTRAORDINARY GENERAL MEETING AND THE ALLERGAN SPECIAL MEETING

The following are answers to certain questions you may have regarding the transactions,Merger and the Actavis extraordinary generalspecial meeting of the stockholders of KYTHERA to be held on [●], 2015 at [●] local time, at [●] (referred to in this joint proxy statement/prospectus as the “Actavis EGM”) and the Allergan“KYTHERA special meeting.meeting”). You are urged to read carefully this entire joint proxy statement/prospectus, because the information in this section may not provide all of the information that might be important to you in determining how to vote. Additional important information is also contained in the Annexes to, and the documents incorporated by reference into, this joint proxy statement/prospectus. See the section entitled “Where You Can Find More Information” beginning on page [—●] of this joint proxy statement/prospectus. All references in this joint proxy statement/prospectus to “Actavis”“Allergan” refer to ActavisAllergan plc, an Irish public limited company,company; all references to “Merger Sub” refer to Avocado AcquisitionKeto Merger Sub, Inc., a Delaware corporation and an indirect wholly owned subsidiary of Actavis, andAllergan; all references to “Allergan”“KYTHERA” refer to Allergan,KYTHERA Biopharmaceuticals, Inc., a Delaware corporation; all references to the “Merger Agreement” refer to the Agreement and Plan of Merger, dated November 16, 2014,as of June 17, 2015, by and among Actavis,Allergan, Merger Sub and KYTHERA, as amended by Amendment No. 1, dated as of July 1, 2015, by and among Allergan, (asMerger Sub and KYTHERA (referred to in this proxy statement/prospectus as “Amendment No. 1”), as it may be further amended from time to time)time, a copy of which is included as Annex A to this jointproxy statement/prospectus; and all references to the “Voting Agreement” refer to the Stockholder Voting Agreement, dated as of June 17, 2015, by and between Allergan and each of the individuals or entities listed on the signature pages thereto, as it may be amended from time to time, a copy of which is included as Annex B to this proxy statement/prospectus. Unless otherwise indicated, all references to “dollars” or “$” in this joint proxy statement/prospectus are references to U.S. dollars. If you are in any doubt about this transaction you should consult an independent financial advisor who, if you are obtaining advice in Ireland, is authorized or exempted by the Investment Intermediaries Act 1995, or the European Communities (Markets in Financial Instruments) Regulations (Nos. 1 to 3) 2007 (as amended).advisor.

A: ActavisAllergan has agreed to acquire AllerganKYTHERA under the terms of the Merger Agreement. Pursuant to the Merger Agreement, Merger Sub will merge with and into AllerganKYTHERA (which merger is referred to in this joint proxy statement/prospectus as the “Merger”), with AllerganKYTHERA continuing as the surviving corporation (referred to in this joint proxy statement/prospectus as the “Surviving Corporation”). Following the Merger, AllerganKYTHERA will be an indirect wholly owned subsidiary of ActavisAllergan and the AllerganKYTHERA common stock will be delisted from the New York Stock ExchangeThe NASDAQ Global Select Market (referred to in this joint proxy statement/prospectus as the “NYSE”“NASDAQ”), deregistered under the Securities Exchange Act of 1934, as amended (referred to in this joint proxy statement/prospectus as the “Exchange Act”) and cease to be publicly traded.

Actavis shareholders and Allergan stockholders are being asked to vote on distinct issues. Actavis shareholders are being asked to approve (i) the issuance of Actavis ordinary shares pursuant to the Merger Agreement and (ii) the adjournment of the Actavis EGM and any adjournments thereof. AllerganKYTHERA stockholders are being asked to (i) adopt the Merger Agreement, (ii) approve the adjournment of the AllerganKYTHERA special meeting to another date and place if necessary or appropriate to solicit additional votes in favor of adopting the Merger Agreement, and (iii) approve, on a non-binding, advisory basis, the compensation payments that will or mayto be paid by AllerganKYTHERA to its named executive officers that is based on or otherwise relates to the Merger.

The approval by the Actavis shareholders of the issuance of Actavis ordinary shares pursuant to the Merger Agreement and the adoption of the Merger Agreement by the AllerganKYTHERA stockholders are conditionsis a condition to the completionconsummation of the Merger. See the section entitled “The Merger Agreement—Conditions to the CompletionConsummation of the Merger” beginning on page [—[●] of this joint proxy statement/prospectus.

A: Each of Actavis and AllerganKYTHERA is sending these materials to its respective shareholders or stockholders to help them decide how to vote their Actavis ordinary shares or Allerganof KYTHERA common stock as the case may be, with respect to matters to be considered at the Actavis EGM and the AllerganKYTHERA special meeting, respectively.

CompletionThe consummation of the Merger requires the approval of both the Actavis shareholders and the AllerganKYTHERA stockholders. To obtain the required shareholder and stockholder approvals, Actavisapproval, KYTHERA will hold the Actavis EGMKYTHERA special meeting at which ActavisKYTHERA will ask its shareholders to approve (i) the issuance of Actavis ordinary shares pursuant to the Merger Agreement and (ii) the adjournment of the Actavis EGM, and any adjournments thereof, and Allergan will hold a special meeting of stockholders at which Allergan will ask its

stockholders to approve (i) the adoption of the Merger Agreement, (ii) the adjournment of the AllerganKYTHERA special meeting to another date and place if necessary or appropriate to solicit additional votes in favor of adopting the Merger Agreement, and (iii) a non-binding, advisory proposal relating to the compensation payable to Allergan’sbe paid by KYTHERA to its named executive officers that is based on or otherwise relates to the Merger. Further information about the Actavis EGM, the AllerganKYTHERA special meeting and the Merger is contained in this joint proxy statement/prospectus. The Merger is not conditioned on the approval of the adjournment of the Actavis EGM or the approval of the adjournment of the AllerganKYTHERA special meeting or the compensation payable to Allergan’sKYTHERA’s named executive officers that is based on or otherwise relates to the Merger.

This joint proxy statement/prospectus constitutes both a joint proxy statement of Actavis and AllerganKYTHERA and a prospectus of Actavis.Allergan. It is a joint proxy statement because each of the boardsboard of directors of Actavis and AllerganKYTHERA (referred to in this proxy statement/prospectus as the “KYTHERA Board”) is soliciting proxies from its respective shareholders or stockholders in connection with the KYTHERA special meeting using this joint proxy statement/prospectus. It is a prospectus because Actavis,Allergan, in connection with the Merger Agreement, is offering its ordinary shares in partial exchange for the outstanding shares of AllerganKYTHERA common stock in the Merger.

The enclosed proxy materials allow you to grant a proxy or vote your shares by telephone or Internet without attending your respective company’s EGM orthe KYTHERA special meeting in person.

Your vote is very important. You are encouraged to submit your proxy or vote your shares by telephone or Internet as soon as possible, even if you do plan to attend the Actavis EGM or the AllerganKYTHERA special meeting in person.

For the avoidance of doubt, this joint proxy statement/prospectus is not intended to be and is not a prospectus for the purposes of the Investment Funds, Companies and Miscellaneous Provisions Act of 2005 of Ireland (referred to in this joint proxy statement/prospectus as the “2005 Act”), the Prospectus (Directive 2003/71/EC) Regulations 2005 of Ireland (as amended) or the Prospectus Rules issued under the 2005 Act, and the Central Bank of Ireland has not approved this joint proxy statement/prospectus.

A: As a result of the Merger, each share of KYTHERA common stock issued and outstanding shareimmediately prior to the effective time of Allergan common stock,the Merger, other than (i) any shares of Allergan commonheld by KYTHERA as treasury stock held in the treasury of Allergan or owned by Actavis,Allergan or Merger Sub or by any of their respective wholly owned subsidiaries, which will each be cancelledcanceled without consideration, and ceaseany shares subject to exist, and no consideration willany unvested KYTHERA restricted stock award which is to be deliveredassumed by Allergan in exchange thereforthe Merger (the shares described in (i) are referred to in this joint proxy statement/prospectus as “excluded shares”) and (ii) shares of AllerganKYTHERA common stock held by AllerganKYTHERA stockholders who have properly demanded appraisal and otherwise complied with applicable Delaware law and not effectively withdrawn any demand for, or lost the right to, appraisal under Delaware law, which will become entitled to the payment of the fair value of such shares determined in accordance with Delaware law as described under the section entitled “Appraisal Rights” beginning on page [—[●] of this joint proxy statement/prospectus (the shares described in (ii) are referred to in this joint proxy statement/prospectus as “dissenting shares”), will be converted into the right to receive 0.3683 of an Actavis ordinary share (referred to in this joint proxy statement/prospectus as the “Stock Consideration Portion”) and $129.22(1) $60.00 in cash, without interest (referred to in this joint proxy statement/prospectus as the “Cash Consideration Portion,”Portion”) and (2) that number of validly issued, fully paid and nonassessable ordinary shares of Allergan (referred to in this proxy statement/prospectus as “Allergan ordinary shares”) equal to the Stockquotient determined by dividing $15.00 by the volume weighted average price of Allergan ordinary shares (as reported by Bloomberg L.P. or, if not reported by Bloomberg L.P., in another authoritative source mutually selected by Allergan and KYTHERA) for a ten trading day period, starting with the opening of trading on the twelfth trading day prior to the closing date of the Merger (referred to in this proxy statement/prospectus as the “Closing Date”) and ending with the closing of trading on the third to last trading day prior to the Closing Date (such volume weighted average price of Allergan ordinary shares is referred to in this proxy statement/prospectus as the “Allergan VWAP”), and rounding the result to the nearest 1/10,000 of an Allergan ordinary share (referred to in this proxy statement/prospectus as the “Stock Consideration PortionPortion” and, collectively with the Cash Consideration Portion, are collectively referred to in this joint proxy statement/prospectus as the “Merger Consideration”). It is anticipated that Actavis shareholders and Allergan stockholders, in each case as of immediately prior to the Merger, will hold approximately [—]% and [—]%, respectively, of the issued and outstanding Actavis ordinary shares immediately after completion of the Merger, based on the number of Actavis ordinary shares and Allergan shares of common stock outstanding as of [—], 2015.

No holder of AllerganKYTHERA common stock will be issued fractional ActavisAllergan ordinary shares in the Merger. Each holder of AllerganKYTHERA common stock converted pursuant to the Merger who would otherwise have been entitled to

receive a fraction of an ActavisAllergan ordinary share will receive, in lieu thereof, cash, without interest, in an amount equal to such fractional part of an ActavisAllergan ordinary share (rounded to the nearest one thousandth when expressed in decimal form) multiplied by the volume weighted average price of Actavis ordinary shares for a 10 trading day period, starting with the opening of trading on the 11^th trading day prior to the closing date to the closing of trading on the second to last trading day prior to the closing date, as reported by Bloomberg (referred to in this joint proxy statement/prospectus as the “Actavis VWAP”).Allergan VWAP.

A: BecauseIn the Merger, Consideration includes a fixed fraction of aeach KYTHERA stockholder will receive, for each share of Actavis ordinary shares, the exact valueKYTHERA common stock they own as of the Merger Consideration that Allergan stockholders will receive as a result of the Merger will depend in part on the price per share of Actavis ordinary shares atimmediately prior to the effective time of the Merger. ThisMerger, other than excluded shares and dissenting shares, (i) the Cash Consideration Portion and (ii) the Stock Consideration Portion, as described above.

The Allergan VWAP, which will be used to determine the fraction of an Allergan ordinary share comprising the Stock Consideration Portion, may be different, and may be lower, than the market price willof Allergan ordinary shares on the date KYTHERA stockholders receive their Allergan ordinary shares, the date the Merger Agreement was executed, the date of this proxy statement/prospectus or the date of the KYTHERA special meeting. Changes in the market price of Allergan ordinary shares may result from changes in the business, operations or prospects of Allergan, market reactions to the proposed Merger and market assessments of its likelihood of being completed, regulatory considerations or developments, general market or economic conditions or other factors.

While the exact number of Allergan ordinary shares to be received by KYTHERA stockholders as the Stock Consideration Portion of the Merger Consideration may not be known at the time of the Actavis EGM orKYTHERA special meeting because the Allergan special meetingVWAP cannot be determined until the closing of trading on the third to last trading day prior to the Closing Date, the KYTHERA stockholders have certainty that the Stock Consideration Portion will represent Allergan ordinary shares with $15.00 in value, based on the Allergan VWAP, for each share of KYTHERA common stock, other than excluded shares and maydissenting shares, held by each KYTHERA stockholder.

The exchange ratio mechanism effectively provides for the Stock Consideration Portion of the Merger Consideration to have a “fixed value.” As a result of the exchange ratio mechanism, KYTHERA stockholders have protection against declines in the price per Allergan ordinary share between execution of the Merger Agreement and the beginning of the ten day trading period that determines the Allergan VWAP, because a lower Allergan VWAP will result in a greater fraction of an Allergan ordinary share being issuable as stock consideration. However, the value of the Stock Consideration Portion (based on the Allergan VWAP) will not be greater than less than, or$15.00 per share of KYTHERA common stock even if the sameprice per Allergan ordinary share increases between execution of the Merger Agreement and the closing of the Merger, because a higher Allergan VWAP will result in a smaller fraction of an Allergan ordinary share being issuable as stock consideration. Moreover, the currentvalue of such stock consideration, based on the actual trading price or the priceper share of Allergan ordinary shares at the time of the Actavis EGM orclosing of the Merger, could be less (or more) than $15.00 due to potential variances between the Allergan VWAP and the actual trading price per Allergan ordinary share at the closing of the Merger.

No holder of KYTHERA common stock will be issued fractional Allergan ordinary shares in the Merger. Each holder of KYTHERA common stock who would otherwise have been entitled to receive a fraction of an Allergan ordinary share will receive, in lieu thereof, cash, without interest, in an amount equal to such fractional part of an Allergan ordinary share (rounded to the nearest one thousandth when expressed in decimal form) multiplied by the Allergan VWAP.

During the twelve-month period ending on [●], 2015, the record date for the KYTHERA special meeting. Based onmeeting, the closing price per share of ActavisAllergan ordinary shares on the NYSE on November 14, 2014, the last full trading day before the public announcementvaried from a low of the signing$[●] to a high of the Merger Agreement, the Merger Consideration represented $219.00 in value for each share of Allergan common stock. Based on the closing price per share of Actavis ordinary shares on [—$[●], 2015, the most recent practicable trading day priorand ended that period at $[●]. KYTHERA encourages you to the date of this joint proxy statement/prospectus, the Merger Consideration represented $[—] in value for each share of Allergan common stock. You should obtain current stock pricemarket quotations for ActavisAllergan ordinary shares and AllerganKYTHERA common stock before deciding how toyou vote with respect to the issuance of Actavis ordinary shares or the adoption of the Merger Agreement, as applicable; however, as noted above, the price of Actavis ordinary shares at the effective time of the Merger may be greater than, less than or the same as such stock price quotations.your shares.

A:Stock Options: AtAs of the effective time of the Merger, each outstanding option to purchase AllerganKYTHERA common stock (referred to in this joint proxy statement/prospectus as an “Allergana “KYTHERA Stock Option”) heldgranted under any KYTHERA equity plan that is outstanding and unexercised immediately prior to the effective time of the Merger, whether or not then vested or exercisable and other than as described in the next paragraph for certain vested KYTHERA Stock Options, will be assumed by an employee of Allergan and/or its subsidiaries who continues to be employed by Actavis or the Surviving Corporation or any subsidiary thereof (such employees of Allergan and/or its subsidiaries referred to in this joint proxy statement/prospectus as the “Continuing Employees”)and will be converted into an option to purchase a number of ActavisAllergan ordinary shares determined(referred to in this proxy statement/prospectus as an “Allergan Stock Option”) and will remain subject to the same vesting (if unvested) and other terms and conditions as applied to the applicable KYTHERA Stock Option immediately prior to the effective time of the Merger (but taking into account any changes thereto provided for in the applicable KYTHERA equity plan, in any award agreement or in the KYTHERA Stock Option by multiplyingreason of the Merger Agreement or the Merger, including the Equity Award Amendment (as defined in “The Merger—Interests of KYTHERA’s Directors and Executive Officers after the Merger—Treatment of KYTHERA Stock Options and Other KYTHERA Equity Awards” beginning on page [●] of this proxy statement/prospectus)). As of the effective time of the Merger, each such Allergan Stock Option as so assumed and converted will be exercisable for that whole number of Allergan ordinary shares equal to the product (which product will be rounded down to the nearest whole share) of (i) the number of shares of AllerganKYTHERA common stock subject to such AllerganKYTHERA Stock Option immediately prior to the effective time of the Merger multiplied by (ii) the quotient determined by dividing $75.00 by the sumAllergan VWAP, and rounding the result to the nearest 1/10,000 of (i) the Stock Consideration Portion and (ii) a fraction, the numerator of which is the Cash Consideration Portion and the denominator of which is the Actavis VWAP (the sum of (i) and (ii) isan Allergan ordinary share (such quotient referred to in this joint proxy statement/prospectus as the “Stock Award Exchange Ratio”), and with aat an exercise price per Allergan ordinary share equal to the quotient (which quotient will be rounded down to the nearest whole cent) obtained by dividing (x) the exercise price per share exercise price equal to (i) the per share exercise price of the AllerganKYTHERA common stock of such KYTHERA Stock Option divided by (ii)(y) the Stock Award Exchange Ratio.

At the effective time of the Merger, each vested outstanding AllerganKYTHERA Stock Option held by an Allergana KYTHERA non-employee director or any employee of KYTHERA who does not continue to be employed by the Surviving Corporation or any other affiliate of Allergan who is not a Continuing Employeefollowing the effective time of the Merger (such non-continuing employees of KYTHERA referred to in this proxy statement/prospectus as the “Non-Continuing Employees”) will vest in full and be cancelled and converted into the right to receive an amount in cash, per sharewithout interest, equal to the sumproduct determined by multiplying the number of (i)shares of KYTHERA common stock subject to such KYTHERA Stock Option immediately prior to the Stock Consideration Portion multipliedeffective time of the Merger by the Actavis VWAP and (ii)excess, if any, of $75.00 minus the Cash Consideration Portion, minus theper share exercise price of such AllerganKYTHERA Stock Option, subject to applicable withholding taxes. Mr. David Pyott will not be considered a Continuing Employee under the terms of the Merger Agreement. In addition, while it is possible that certain other Allergan executive officers may continue to provide services to Actavis in various non-employee capacities following the effective time of the Merger, such executive officers may not be Continuing Employees under the terms of the Merger Agreement.

Restricted StockShare Awards: AtAs of the effective time of the Merger, each outstanding KYTHERA restricted share of Allergan common stock award (referred to in this joint proxy statement/prospectus as an “Allergana “KYTHERA Restricted Share”Share Award”) heldgranted under any KYTHERA equity plan that is not then vested will be assumed by a Continuing EmployeeAllergan and will be converted into a numberan award of restricted ActavisAllergan ordinary shares (referred to in this joint proxy statement/prospectus as “Actavis“Allergan Restricted Shares”Share Awards”) determined by multiplying the number of shares of Allergan Restricted Shares by the Stock Award Exchange Ratio,, and will remain subject to the same terms and

conditions as applied to the Allergan Restricted Shares. At the effective time of the Merger, each Allergan Restricted Share that is held by an Allergan non-employee director or any employee of Allergan who is not a Continuing Employee will vest in full and the holder will be entitled to receive the Merger Consideration, subject to applicable withholding taxes.

Restricted Stock Units: At the effective time of the Merger, each outstanding Allergan restricted stock unit (referred to in this joint proxy statement/prospectus as an “Allergan RSU”) held by a Continuing Employee will be converted into a restricted stock unit award for Actavis ordinary shares (each referred to in this joint proxy statement/prospectus as an “Actavis RSU”) determined by multiplying the number of shares of Allergan common stock underlying the Allergan RSU by the Stock Award Exchange Ratio, and will remain subject to the same terms and conditions as applied to the Allergan RSU. Performance in respect of any Allergan RSUs that are subject to performance-based vesting will be deemed achieved based on target performance, provided that all converted Allergan RSUs subject to performance-based vesting will vest on the last day of the applicable performance period and will remain subject to the same terms and conditions as applied to the Allergan RSUsKYTHERA Restricted Share Award immediately prior to the effective time of the Merger.Merger (but taking into account any changes thereto provided for in the applicable KYTHERA equity plan, in any award agreement or in the KYTHERA Restricted Share Award by reason of the Merger Agreement or the Merger, including the Equity Award Amendment). As of the effective time of the Merger, the number of Allergan ordinary shares underlying each Allergan Restricted Share Award will be equal to the product (which will be rounded up to the nearest whole share) of the number of shares of KYTHERA common stock subject to the applicable KYTHERA Restricted Share Award multiplied by the Stock Award Exchange Ratio.

Restricted Stock Unit Awards: As of the effective time of the Merger, each outstanding KYTHERA restricted stock unit award (referred to in this proxy statement/prospectus as a “KYTHERA RSU Award” and collectively with KYTHERA Stock Options and KYTHERA Restricted Share Awards, as “KYTHERA Equity Awards”) issued under any KYTHERA equity plan that is not then vested will be assumed by Allergan and will be converted into a restricted stock unit award for Allergan ordinary shares (each referred to in this proxy statement/prospectus as an “Allergan RSU Award”), and each Allergan RSU Award will remain subject to the same terms

and conditions as applied to the applicable KYTHERA RSU Award immediately prior to the effective time of the Merger (but taking into account any changes thereto provided for in the applicable KYTHERA equity plan, in any award agreement or in the KYTHERA RSU Award by reason of the Merger Agreement or the Merger, including the Equity Award Amendment). As of the effective time of the Merger, the number of Allergan ordinary shares underlying each Allergan RSU Award will be equal to the product (which will be rounded up to the nearest whole share) of the number of shares of KYTHERA common stock underlying the applicable KYTHERA RSU Award multiplied by the Stock Award Exchange Ratio. Further, ActavisAllergan will have the ability to adjust any dividend equivalent rights under anyassociated with the Allergan equity plan, in any award agreement or in any Allergan RSUs,RSU Awards, to reflect dividends on Allergan ordinary shares giving effect to the changes orand adjustments contemplated to the corresponding Allergan RSUsKYTHERA RSU Awards by reason of the Merger Agreement or the Merger. At

See the effective timesection entitled “The Merger Agreement—Treatment of the Merger, each Allergan RSU that is held by an Allergan non-employee director or any employee of Allergan who is not a Continuing Employee will vest in fullKYTHERA Stock Options and the holder will be entitled to receive the Merger Consideration, subject to applicable withholding taxes.

See “The Merger—Interests of Allergan’s Directors and Executive Officers in the TransactionOther KYTHERA Equity Awards” beginning on page [—●] of this joint proxy statement/prospectus.

A: The parties currently expect that the Merger will be completedconsummated during the secondthird quarter of 2015. Neither ActavisAllergan nor AllerganKYTHERA can predict, however, the actual date on which the Merger will be completed,consummated, or whether it will be completed,consummated, because the Merger is subject to factors beyond each company’s control, including whether or when the required regulatoryantitrust approvals will be received. See the section entitled “The Merger Agreement—Conditions to the CompletionConsummation of the Merger” beginning on page [—[●] of this joint proxy statement/prospectus.

A:Actavis: The board of directors of ActavisKYTHERA Board has fixed [—]the close of business on [—[●], 2015 as the record date of the Actavis EGMKYTHERA special meeting (referred to in this joint proxy statement/prospectus as the “Actavis record“record date”). If you were an Actavis shareholdera KYTHERA stockholder of record as of [—]the close of business on [—[●], 2015, you are entitled to receive notice of and to vote at the Actavis EGM and any adjournments thereof.

Allergan: The board of directors of Allergan has fixed [—] on [—], 2015 as the record date of the Allergan special meeting (referred to in this joint proxy statement/prospectus as the “Allergan record date”). If you were an Allergan stockholder of record as of [—] on [—], 2015, you are entitled to receive notice of and to vote at the AllerganKYTHERA special meeting and any adjournments thereof.

A: Actavis shareholders are being asked to vote on the following proposals:

2.

to approve the adjournment of the Actavis EGM, or any adjournments thereof, to another time and place if necessary or appropriate to, among other things, solicit additional proxies if there are insufficient votes at the time of the Actavis EGM to approve the Actavis Share Issuance Proposal (referred to in this joint proxy statement/prospectus as the “Actavis Adjournment Proposal” and the Actavis Share Issuance Proposal and the Actavis Adjournment Proposal collectively referred to in this joint proxy statement/prospectus as the “Actavis EGM Resolutions”). The Merger Agreement provides that Actavis may not postpone or adjourn the Actavis EGM to a date that is more than 30 days after the date on which the Actavis EGM was originally scheduled.

Under the NYSE rules, shareholder approval is required prior to the issuance of stock if the number of shares of stock to be issued in a transaction equals 20% or more of the number of shares of stock outstanding prior to the issuance. The issuance of ordinary shares by Actavis pursuant to the Merger Agreement will result in the issuance of a number of ordinary shares equal to approximately [—]% of the Actavis ordinary shares expected to be outstanding prior to the Merger. Accordingly, Actavis shareholders are being asked to consider and vote on the issuance of Actavis ordinary shares pursuant to the Merger Agreement. Actavis shareholder approval of the Actavis Share Issuance Proposal is required to complete the Merger under the terms of the Merger Agreement.

Under Irish law, Actavis shareholders are not required to approve the Merger or adopt the Merger Agreement. Accordingly, Actavis shareholders are not being asked to vote on the Merger or the adoption of the Merger Agreement.

No other matters are intended to be brought before the Actavis EGM by Actavis.

A:The Actavis Share Issuance Proposal: The affirmative vote of a majority of the votes cast, either in person or by proxy, by shareholders entitled to vote on the Actavis Share Issuance Proposal at the Actavis EGM is required to approve the Actavis Share Issuance Proposal.

The Actavis Adjournment Proposal: The affirmative vote of a majority of the votes cast, either in person or by proxy, by shareholders entitled to vote on the Actavis Adjournment Proposal at the Actavis EGM is required to approve the Actavis Adjournment Proposal.

Because the vote required to approve each of the Actavis Share Issuance Proposal and the Actavis Adjournment Proposal is based on votes properly cast at the Actavis EGM, and because abstentions are not considered votes properly cast, abstentions, along with failures to vote, will have no effect on such proposals (except that failures to vote will not, but abstentions will, be counted towards determining whether a quorum is present).

A: The Actavis board of directors has unanimously approved the Merger Agreement and determined that the Merger Agreement and the transactions contemplated by the Merger Agreement, including the Merger, are in the best interests of Actavis and its shareholders. The Actavis board of directors unanimously recommends that the Actavis shareholders vote their Actavis ordinary shares:

Q:	ARE THERE ANY RISKS ABOUT THE MERGER OR ALLERGAN’S BUSINESS THAT ACTAVIS SHAREHOLDERS SHOULD CONSIDER IN DECIDING WHETHER TO VOTE ON THE PROPOSALS?

A: Yes. Before making any decision on whether and how to vote, Actavis shareholders are urged to read carefully and in its entirety “Risk Factors” beginning on page [—] of this joint proxy statement/prospectus. Actavis shareholders should also read and carefully consider the risk factors of Actavis and Allergan and the other risk factors that are incorporated by reference into this joint proxy statement/prospectus.

A: AllerganKYTHERA stockholders are being asked to vote on the following proposals:

AllerganKYTHERA stockholder approval of the Merger Proposal is required for completionconsummation of the Merger. Allergan

KYTHERA stockholder approval of the Allergan Adjournment Proposal and the Merger-Related Named Executive Officer Compensation Proposal is not required for completionconsummation of the Merger. No other matters are intended to be brought before the AllerganKYTHERA special meeting by Allergan.meeting.

The Merger Agreement provides that AllerganKYTHERA may not postpone or adjourn the AllerganKYTHERA special meeting to a date that is more than 30 days after the date on which the AllerganKYTHERA special meeting was originally scheduled.

A:The Merger Proposal: The affirmative vote of a majority of the outstanding shares of AllerganKYTHERA common stock entitled to vote on the proposal at the Allergan special meetingheld by stockholders of record as of [●], 2015 is required to approve the Merger Proposal. If you are an Allergana KYTHERA stockholder and you abstain from voting or fail to vote, or fail to instruct your broker, bank or other nominee how to vote on the Merger Proposal, it will have the same effect as a vote cast against the Merger Proposal.

The Allergan Adjournment Proposal: TheAssuming a quorum is present, the affirmative vote of at least a majority of the votes cast with respect to shares of AllerganKYTHERA common stock entitledat the KYTHERA special meeting is required to vote onapprove the proposalAdjournment Proposal. For the Adjournment Proposal, if a KYTHERA stockholder is present in person or by proxy at the AllerganKYTHERA special meeting is requiredand chooses to approveabstain from voting with respect to the Allergan Adjournment Proposal. For the Allergan Adjournment Proposal, an abstentionit will have no effect on the same effect asoutcome of the Adjournment Proposal (except that the fact that such stockholder is present in person or by proxy at the KYTHERA special meeting will be counted in determining whether a vote cast against this proposal.quorum is present). If an Allergana KYTHERA stockholder fails to vote and is not present in person or by proxy at the AllerganKYTHERA special meeting, it will have no effect on the vote count for the Allergan Adjournment Proposal (except that itthe fact that such stockholder is not present in person or by proxy at the KYTHERA special meeting will not be counted towardsin determining whether a quorum is present).

The Merger-Related Named Executive Officer Compensation Proposal: TheAssuming a quorum is present, the affirmative vote of a majority of the votes cast with respect to shares of AllerganKYTHERA common stock entitled to vote on the proposal present in person or by proxy at the AllerganKYTHERA special meeting is required to approve the Merger-Related Named Executive Officer Compensation Proposal. The KYTHERA stockholders’ vote regarding the Merger-Related Named Executive Officer Compensation Proposal is an advisory vote, and therefore is not binding on AllerganKYTHERA or the board of directorsKYTHERA Board or the compensation committee of Allergan.KYTHERA. Since compensation and benefits to be paid or provided in connection with the Merger are based on contractual arrangements with the named executive officers, the outcome of this advisory vote will not affect the obligation to make these payments and these payments may still be made even if the AllerganKYTHERA stockholders do not approve, by advisory(non-binding) vote, the Merger-Related Named Executive Officer Compensation Proposal. For the Merger-Related Named Executive Officer Compensation Proposal, an abstentionif a KYTHERA stockholder is present in person or by proxy at the KYTHERA special meeting and chooses to abstain from voting with respect to the Merger-Related Named Executive Officer Compensation Proposal, it will have no effect on the same effect asoutcome of the Merger-Related Named Executive Officer Compensation Proposal (except that the fact that such stockholder is present in person or by proxy at the KYTHERA special meeting will be counted in determining whether a vote against the proposal.quorum is present). If an Allergana KYTHERA stockholder fails to vote and is not present in person or by proxy at the AllerganKYTHERA special meeting, it will have no effect on the vote count for the Merger-Related Named Executive Officer Compensation Proposal (except that itthe fact that such stockholder is not present in person or by proxy at the KYTHERA special meeting will not be counted towardsin determining whether a quorum is present).

A: In connection with the Merger, each of KYTHERA’s directors and certain of their affiliates (referred to in this proxy statement/prospectus as the “Supporting Stockholders”) entered into the Voting Agreement with Allergan. Pursuant to the Voting Agreement, each Supporting Stockholder has agreed, among other things, to vote his, her or its shares of KYTHERA common stock in favor of the Merger Proposal and the Adjournment Proposal. As of the record date, the Supporting Stockholders owned in the aggregate approximately [●] shares of KYTHERA common stock (not including any shares of KYTHERA common stock subject to KYTHERA Stock Options), representing approximately [●]% of the shares of KYTHERA common stock outstanding as of the close of

business on the record date. The Voting Agreement does not change the number of votes required to approve the Merger Proposal or the Adjournment Proposal. See the section entitled “The Voting Agreement” beginning on page [●] of this proxy statement/prospectus.

A: The Allergan board of directorsKYTHERA Board has unanimously approved the Merger Agreement and determined that the Merger Agreement and the transactions contemplated by the Merger Agreement,thereby, including the Merger, are advisable, fair and reasonableto, and in the best interests of AllerganKYTHERA and its stockholders. The Allergan board of directorsthe KYTHERA stockholders, has unanimously approved and declared advisable the Merger Agreement and the transactions contemplated thereby, including the Merger, on the terms and subject to the conditions set forth therein, and unanimously recommends that AllerganKYTHERA stockholders vote their shares of AllerganKYTHERA common stock:

1. “FOR” the Merger Proposal;

2. “FOR” the Allergan Adjournment Proposal; and

3. “FOR” the Merger-Related Named Executive Officer Compensation Proposal.

A: Yes. Before making any decision on whether and how to vote, AllerganKYTHERA stockholders are urged to read carefully and in its entirety the section entitled “Risk Factors” section beginning on page [—[●] of this joint proxy statement/prospectus. AllerganKYTHERA stockholders should also read and carefully consider the risk factors of ActavisKYTHERA and Allergan and the other risk factors that are incorporated by reference into this joint proxy statement/prospectus.

A: Yes. Allergan’sKYTHERA’s directors and executive officers have interests in the Merger that are different from, or in addition to, theirthe interests as Allerganof KYTHERA stockholders. See the section entitled “The Merger—Interests of Allergan’sKYTHERA’s Directors and Executive Officers in the TransactionsMerger” beginning on page [—[●] of this joint proxy statement/prospectus. The members of Allergan’s board of directorsKYTHERA’s Board were aware of and considered these interests, among other matters, in evaluating the Merger Agreement and the Merger and in recommending that AllerganKYTHERA stockholders vote to adopt the Merger Agreement.

A: After carefully reading and considering the information contained or incorporated by reference in this joint proxy statement/prospectus, please submit your proxy or voting instruction card for your shares as soon as possible so that your shares of KYTHERA common stock entitled to vote at the KYTHERA special meeting will be represented at your respective company’s meeting of shareholders or stockholders.represented. Please follow the

instructions set forth on the proxy card or on the voting instruction card provided by the record holder if your shares are held in “street name” through your broker, bank or other nominee.

A: If you are a shareholder of record as of the Actavis record date, or a stockholder of record of AllerganKYTHERA as of the Allergan record date, you may submit your proxy before your respective company’s extraordinary general meeting orthe KYTHERA special meeting in one of the following ways:

1.

2. call the toll-free number for telephone proxy submission shown on your proxy card; or

3. complete, sign, date and return the enclosed proxy card in the enclosed postage-paid envelope.

You may also cast your vote in person at your respective company’s extraordinary general meeting orthe KYTHERA special meeting.

If your shares are held in “street name,” through a broker, bank or other nominee, that institution will send you separate instructions describing the procedure for voting your shares. “Street name” shareholders or stockholders who wish to vote in person at the meeting will need to obtain a proxy form from their broker, bank or other nominee.

A:Actavis: You are entitled to one vote for each Actavis ordinary share that you owned as of [—] on the Actavis record date. As of [—] on the Actavis record date, [—] Actavis ordinary shares were outstanding and entitled to vote at the Actavis EGM.

Allergan: You are entitled to one vote for each share of AllerganKYTHERA common stock that you owned as of [—[●] on, the Allergan record date. As of [—]the close of business on the Allergan record date, [—[●] shares of AllerganKYTHERA common stock were outstanding and entitled to vote at the Allergan special meeting.outstanding.

A:Actavis: If you transfer your Actavis ordinary shares after the Actavis record date but before the Actavis EGM, you will, unless you provide the transferee of your shares with a proxy, retain your right to vote at the Actavis EGM.

Allergan: If you transfer your shares of AllerganKYTHERA common stock after the Allergan record date but before the AllerganKYTHERA special meeting, you will, unless you provide the transferee of your shares with a proxy, retain your right to vote at the AllerganKYTHERA special meeting but will have transferred the right to receive the Merger Consideration. In order to receive the Merger Consideration, you must hold your shares through the effective time of the Merger.

A: No. To the extent certain AllerganKYTHERA stockholders have certificated shares, such AllerganKYTHERA stockholders should keep their existing stock certificates at this time. After the Merger is completed, AllerganKYTHERA stockholders will receive a letter of transmittal and written instructions for exchanging their stock certificates for ActavisAllergan ordinary shares and the cash portion of the Merger Consideration.

Q:	WHEN AND WHERE AREIS THE ACTAVIS EXTRAORDINARY GENERAL MEETING OF SHAREHOLDERS AND THE ALLERGANKYTHERA SPECIAL MEETING OF STOCKHOLDERS?MEETING?

A:Actavis: The Actavis EGMKYTHERA special meeting will be held at [—[●], at [—[●], (local time), on [—[●], 2015.

Allergan:

A: The special meeting of Allergan stockholders will be held at [—], at [—], (local time), on [—], 2015.

Q: WHAT CONSTITUTES A QUORUM?

A:Actavis: The presence of two or more persons holding or representing by proxy (whether or not such holder actually exercises his voting rights in whole, in part or at all) more than 50% of the total issued voting rights of Actavis’ shares. Abstentions will be counted as present for purposes of determining whether there is a quorum.

Allergan: The presence, in person or by proxy, of the holders of a majority in voting interestpower of the issued and outstanding AllerganKYTHERA common stock entitled to vote that are present in person or represented by proxy will constitute a quorum for the KYTHERA special meeting. Abstentions are considered present for purposes of determining a quorum. As of the record date, [●] shares of KYTHERA common stock were outstanding, thus [●] shares present in person or represented by proxy will constitute a quorum for the meeting.

A: If your shares are held in “street name” in a stock brokerage account or by a bank or other nominee, you must provide the record holder of your shares with instructions on how to vote your shares. Please follow the voting instructions provided by your broker, bank or other nominee. Please note that you may not vote shares held in “street name” by returning a proxy card directly to Actavis or AllerganKYTHERA or by voting in person at your respective company’sthe KYTHERA special meeting unless you obtain a “legal proxy,” which you must obtain from your broker, bank or other nominee.

Under the rules of the NYSE,NASDAQ, brokers who hold shares in “street name” for a beneficial owner of those shares typically have the authority to vote in their discretion on “routine” proposals when they have not received instructions from beneficial owners. However, brokers are not allowed to exercise their voting discretion with respect to the approval of matters that the NYSENASDAQ determines to be “non-routine” without specific instructions from the beneficial owner. It is expected that all proposals to be voted on at the Actavis EGM and the AllerganKYTHERA special meeting will be “non-routine” matters. Broker non-votes occur when a broker or nominee is not instructed by the beneficial owner of shares how to vote on a particular proposal for which the broker does not have discretionary voting power.

If you are an Actavis shareholder and you do not instruct your broker, bank or other nominee on how to vote your shares:

1. your broker, bank or other nominee may not vote your shares on the Actavis Share Issuance Proposal, which broker non-votes will have no effect on the vote count for this proposal (and your shares will not count toward determining whether a quorum is present); and

2. your broker, bank or other nominee may not vote your shares on the Actavis Adjournment Proposal, which broker non-votes will have no effect on the vote count for this proposal (and your shares will not count toward determining whether a quorum is present).

If you are a AllerganKYTHERA stockholder and you do not instruct your broker, bank or other nominee on how to vote your shares:

1. your broker, bank or other nominee may not vote your shares on the Merger Proposal, which broker non-votes will have the same effect as a vote “AGAINST” such proposal;

2. your broker, bank or other nominee may not vote your shares on the Allergan Adjournment Proposal, which broker non-votes will have no effect on the vote count for this proposal (and your shares will not count toward determining whether a quorum is present); and

3. your broker, bank or other nominee may not vote your shares on the Merger-Related Named Executive Officer Compensation Proposal, which broker non-votes will have no effect on the vote count for this proposal (and your shares will not count toward determining whether a quorum is present).

A:Actavis: If you are an Actavis shareholder of record, the shares listed on your proxy card will include the following shares, if applicable:

Please see the Q&A above entitled “How do I vote?” for further information on how to vote such shares.

If your shares are held through a broker, bank or other nominee, that institution will send you separate instructions describing the procedure for voting your shares.

Allergan: If you are an AllerganKYTHERA stockholder of record, the shares listed on your proxy card will include the following shares, if applicable:

Please see the Q&A above entitled “How do I vote?” for further information on how to vote such shares.

If your shares are held through a broker, bank or other nominee, that institution will send you separate instructions describing the procedure for voting your shares.

A: If you are an Actavis shareholder and you fail to vote, fail to submit a proxy or fail to properly instruct your broker, bank or other nominee how to vote on the Actavis Share Issuance Proposal or the Actavis Adjournment Proposal, this will have no effect on the vote count for such proposal (and will not count towards determining whether a quorum is present).

An abstention occurs when a shareholder or stockholder attends the applicable meeting in person and does not vote or returns a proxy or voting instruction card with an “abstain” vote. If you respond with an “abstain” vote on the Actavis Share Issuance Proposal or the Actavis Adjournment Proposal, your proxy will have no effect on the vote count for either proposal, but will count towards determining whether a quorum is present.

If you are an AllerganKYTHERA stockholder and you fail to vote, fail to submit a proxy or fail to return a voting instruction card instructing your broker, bank or other nominee how to vote on the Merger Proposal or you respond with an “abstain” vote on the Merger Proposal, this will have the same effect as a vote cast against the Merger Proposal.

If you are an Allergana KYTHERA stockholder and you fail to vote, fail to submit a proxy or fail to return a voting instruction card instructing your broker, bank or other nominee how to vote on the Allergan Adjournment Proposal or Merger-Related Named Executive Officer Compensation Proposal, this will have no effect on the vote count foroutcome of such proposal (and will not count towards determining whether a quorum is present).proposals. If you respond with an “abstain” vote on the Allergan Adjournment Proposal or Merger-Related Named Executive Officer Compensation Proposal, your proxy will have no effect on the outcome of such proposals.

If you are a KYTHERA stockholder and you fail to vote, fail to submit a proxy or fail to return a voting instruction card instructing your broker, bank or other nominee how to vote on any of the proposals, your shares will not count as present at the KYTHERA special meeting for purposes of determining whether a quorum is present. If you vote against suchon any proposal butor return a voting instruction card, regardless of how you vote, or provide a proxy, your shares will count towardsas present at the KYTHERA special meeting for purposes of determining whether a quorum is present.

Please note, however, if you sign and return your proxy or voting instruction card without indicating how to vote on any particular proposal (and you do not change your vote after delivering your proxy or voting instruction card), the Actavis ordinary shares represented by your proxy will be voted for each Actavis proposal in accordance with the recommendation of the Actavis board of directors or the shares of AllerganKYTHERA common stock represented by your proxy will be voted for each AllerganKYTHERA proposal in accordance with the recommendation of the Allergan board of directors.KYTHERA Board.

Please see the Q&A below entitled “May I change my vote after I have delivered my proxy or voting instruction card?” for further information on how to change your vote.

A:Actavis: Yes. As an Actavis shareholder youYou may change your vote or revoke a proxy at any time before your proxy is voted at the Actavis EGM. If you are an Actavis shareholder of record, you can do this by:

Actavis plc

1 Grand Canal Square, Docklands

Dublin 2, Ireland

Attention: Company Secretary

Attending the Actavis EGM will not automatically revoke a proxy that was submitted through the Internet or by telephone or mail.

If you are an Actavis shareholder whose shares are held in “street name” by a broker, bank or other nominee, you may revoke your proxy and vote your shares in person at the Actavis EGM only in accordance with applicable rules and procedures as employed by such broker, bank or other nominee. If your shares are held in an account at a broker, bank or other nominee, you should contact your broker, bank or other nominee to change your voting instructions.

If you hold shares indirectly in the Actavis benefit plans, you should contact the trustee of your plan, as applicable, to change your vote of the shares allocated to your benefit plan.

Allergan: As an Allergan stockholder you may change your vote or revoke a proxy at any time before your proxy is voted at the AllerganKYTHERA special meeting. If you are an Allergana KYTHERA stockholder of record, you can do this by:

Allergan,KYTHERA Biopharmaceuticals, Inc.

P.O. Box 1953430930 Russell Ranch Road, 3rd floor

Irvine,Westlake Village, California 9262391362

Attention: Keith Klein, Corporate Secretary

If you are an Allergan shareholdera KYTHERA stockholder whose shares are held in “street name” by a broker, bank or other nominee, you may revoke your proxy and vote your shares in person at the AllerganKYTHERA special meeting only in accordance with applicable rules and procedures as employed by such broker, bank or other nominee. If your shares are held in an account at a broker, bank or other nominee, you should contact your broker, bank or other nominee to change your vote.

If you hold shares indirectly in the AllerganKYTHERA benefits plans, you should contact the trustee of your plan, as applicable, to change your vote of the shares allocated to your benefit plan.

Attending the Actavis EGM or the AllerganKYTHERA special meeting will not automatically revoke a proxy that was submitted through the Internet or by telephone or mail.If you wish to change your vote at the Actavis EGM or AllerganKYTHERA special meeting, you must vote by ballot at such meeting to change your vote.

A: Actavis shareholders and AllerganKYTHERA stockholders may receive more than one set of voting materials, including multiple copies of this joint proxy statement/prospectus and multiple proxy cards or voting instruction cards. For example, if you hold Actavis ordinary shares or AllerganKYTHERA common stock in more than one brokerage account, you will receive a separate voting instruction card for each brokerage account in which you hold such shares. If you are a holder of record of Actavis ordinary shares or AllerganKYTHERA common stock and your shares are registered in more than one name, you will receive more than one proxy card. In addition, if you are a holder of both Actavis ordinary shares and Allergan common stock, you will receive one or more separate proxy cards or voting instruction cards for each company.

Please complete, sign, date and return each proxy card and voting instruction card that you receive or otherwise follow the voting instructions set forth in this joint proxy statement/prospectus to ensure that you vote every Actavis ordinary share and/or Allerganof KYTHERA common stock that you own.

A: Preliminary voting results will be announced at the Actavis EGM and the Allergan special meeting, and will be set forth in press releases that Actavis and Allergan intend to issue after the Actavis EGM and the Allergan special meeting, respectively. The respective press releases will be available on the Actavis website atwww.actavis.com and the Allergan website atwww.allergan.com. Final voting results for the Actavis EGM and AllerganKYTHERA special meeting are expected to be published in a Current Report on Form 8-K to be filed by Actavis and AllerganKYTHERA with the SECU.S. Securities and Exchange Commission (referred to this proxy statement/prospectus as the “SEC”) within four business days after the Actavis EGM and the AllerganKYTHERA special meeting, as applicable.meeting. A copy of thesethis Current ReportsReport on Form 8-K will be available after filing with the SEC on the Actavis and Allergan websites, respectively.KYTHERA website.

Q:	ARE ALLERGANKYTHERA STOCKHOLDERS ENTITLED TO APPRAISAL RIGHTS?

A: Yes. AllerganKYTHERA stockholders are entitled to appraisal rights under Section 262 of the General Corporation Law of the State of Delaware (referred to in this joint proxy statement/prospectus as the “DGCL”), provided they do not vote in favor of the Merger Proposal and otherwise satisfy the conditions set forth in Section 262 of the DGCL. More information regarding these appraisal rights is provided in this joint proxy statement/prospectus, and the provisions of Section 262 of the DGCL that grant appraisal rights and govern such procedures are attached as Annex E to this joint proxy statement/prospectus. You should read these provisions carefully and in their entirety. See the section entitled “Appraisal Rights” beginning on page [—[●] of this joint proxy statement/prospectus.

A: No. Actavis shareholders are not entitled to appraisal rights under Irish law in connection with the Merger.

A: For U.S. federal income tax purposes, the exchange of AllerganKYTHERA common stock for ActavisAllergan ordinary shares and cash pursuant to the Merger will be treated as a taxable transaction. AllerganKYTHERA stockholders that are U.S. holders will generally recognize gain or loss equal to the difference, if any, between (i) the sum of (1)(x) the fair market value of the ActavisAllergan ordinary shares received by such holder in the Merger, and (2)(y) the amount of cash received by such holder in the Merger, including any cash received in lieu of fractional shares of ActavisAllergan ordinary shares, and (ii) the stockholder’s tax basis in AllerganKYTHERA common stock surrendered. Such gain or loss generally will be long-term capital gain or loss if the U.S. holder’s holding period of the AllerganKYTHERA common stock surrendered exceeds one year at the effective time of the Merger.

AllerganKYTHERA stockholders should consult their tax advisors as to the particular tax consequences to them of the transactions,Merger, including the effect of U.S. federal, state and local tax laws and foreign tax laws. For a more detailed discussion of the material U.S. federal income tax consequences of the Merger, see the section entitled “Certain Tax Consequences of the Merger—U.S. Federal Income Tax Considerations” beginning on page [—[●] of this joint proxy statement/prospectus.

A: If the Merger is not completed, AllerganKYTHERA stockholders will not receive any consideration for their shares of AllerganKYTHERA common stock. Instead, AllerganKYTHERA will remain an independent public company and its common stock will continue to be listed and traded on NASDAQ. The Merger Agreement contains certain customary termination rights for both KYTHERA and Allergan, including in the NYSE. Underevent that the Merger is not consummated by March 17, 2016 (referred to in this proxy statement/prospectus as the “Outside Date”). The Merger Agreement further provides that, upon termination of the Merger Agreement to accept a competing acquisition proposal and in certain other specified circumstances, Allergan or ActavisKYTHERA may be required to pay to, or be entitled to receive from, the other partyAllergan a termination fee or reimbursement of expenses with respect to the termination of the Merger Agreement,$69.75 million in cash, as described under the section entitled “The Merger Agreement—Termination of the Merger Agreement; Termination Fees; Expense ReimbursementFee” beginning on page [—[●] of this joint proxy statement/prospectus.

A: If you have any questions about the proxy materials or if you need assistance submitting your proxy or voting your shares or need additional copies of this joint proxy statement/prospectus or the enclosed proxy card, you should contact the proxy solicitation agent for the company in which you hold shares.

Actavis shareholders should contact MacKenzie Partners Inc., the proxy solicitation agent for Actavis,KYTHERA, by mail at 105 Madison Avenue, New York, New York 10016. Actavis shareholders may call MacKenzie Partners Inc.NY 10016, or by telephone toll-free at (800) 322-2885 or collect at (212) 929-5500 or toll-free at (800) 322-2885.

Allergan stockholders should contact Innisfree M&A Incorporated, the proxy solicitation agent for Allergan, at 501 Madison Avenue, 20^th Floor, New York, New York 10022. Allergan stockholders may call Innisfree M&A Incorporated collect at (212) 750-5833 or toll-free at (877) 800-5187.929-5500.

A: You can find more information about ActavisAllergan and AllerganKYTHERA from the various sources described under the section entitled “Where You Can Find More Information” beginning on page [—[●] of this joint proxy statement/prospectus.