STX Seagate Technology Holdings PLC

As filed with the Securities and Exchange Commission on October 7, 2015

Registration No. 333-    

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-8

REGISTRATION STATEMENT

Under

The Securities Act of 1933

SEAGATE TECHNOLOGY PUBLIC LIMITED COMPANY

(Exact name of Registrant as specified in its charter)

38/39 Fitzwilliam Square

Dublin 2, Ireland

(Address, including zip code, of Principal Executive Offices)

Dot Hill Systems Corp. 2009 Equity Incentive Plan

(Full title of the plan)

Stephen J. Luczo

Chief Executive Officer, Director and

Chairman of the Board of Directors

Seagate Technology plc

10200 S. De Anza Blvd

P.O. Box 4030

Cupertino, CA 95015

(408) 658-1000

(Name, address and telephone number, including area code, of agent for service)

With copies to:

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

(Check one):

CALCULATION OF REGISTRATION FEE

EXPLANATORY NOTE

We are filing this Registration Statement to register 1,973,638 of our ordinary shares issuable in connection with the Dot Hill Systems Corp 2009 Equity Incentive Plan (the “Dot Hill Plan”).

Pursuant to the Acquisition Agreement, dated as of August 18, 2015 (the “Acquisition Agreement”), by and among Seagate HDD Cayman, an exempted company with limited liability organized under the laws of the Cayman Islands (“Parent”), Denali Acquisition Sub Corp., a Delaware corporation and wholly owned subsidiary of Parent, itself an indirect wholly owned subsidiary of the Registrant (“Purchaser”), and Dot Hill Systems Corp., a Delaware corporation (“Dot Hill”), Purchaser merged with and into Dot Hill on October 6, 2015 (the “Effective Time”). In accordance with the Acquisition Agreement, at the Effective Time, Parent assumed the Dot Hill Plan and certain outstanding options granted under the Dot Hill Plan (the “Assumed Options”). As a result of this assumption, at the Effective Time, the Assumed Options were converted into options of Parent.

PART I

INFORMATION REQUIRED IN THE PROSPECTUS

The information specified in Item 1 and Item 2 of Part I of Form S-8 is omitted from this Registration Statement in accordance with the provisions of Rule 428 under the Securities Act of 1933, as amended (the “Securities Act”), and the introductory note to Part I of Form S-8. The documents containing the information specified in Part I of Form S-8 will be delivered to the participants in the equity benefit plans covered by this Registration Statement as specified by Rule 428(b)(1) under the Securities Act.

PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.  Incorporation of Documents by Reference.

The SEC requires us to “incorporate by reference” certain of our publicly-filed documents into this Registration Statement, which means that information included in those documents is considered part of this Registration Statement. Information that we file with the SEC after the effective date of this Registration Statement will automatically update and supersede this information. We incorporate by reference the documents listed below and future filings made with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) until we terminate the effectiveness of this Registration Statement.

The following documents filed with the SEC are hereby incorporated by reference:

(a)                                 our latest annual report on Form 10-K filed pursuant to Section 13(a) or 15(d) of the Exchange Act, which contains audited financial statements for our latest fiscal year ended July 3, 2015, as filed with the SEC on August 11, 2015;

(b)                              all other reports filed pursuant to Section 13(a) or 15(d) of the Exchange Act since July 3, 2015 (other than information deemed to have been “furnished” rather than “filed” in accordance with the SEC’s rules); and

(c)                                  the description of our Ordinary Shares contained in our Registration Statement on Form 8-A filed with the SEC on December 6, 2002, as amended by Form 8-K12B and Form 8-K12B/A, filed with the SEC on July 6, 2010 and July 9, 2010, respectively.

Any statement contained in a document incorporated by reference herein shall be modified or superseded for purposes of this Registration Statement to the extent that a statement contained herein (or in any other subsequently filed document which also is incorporated by reference herein) modifies or supersedes such statement. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement.

Item 4. Description of Securities.

Not applicable.

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Item 5. Interests of Named Experts and Counsel.

Not applicable.

Item 6.  Indemnification of Directors and Officers.

The articles of association of the Registrant provide for the indemnification of its officers, directors and company secretary. Specifically, under the indemnification provisions, the Registrant will indemnify its officers, directors and company secretary to the fullest extent permitted by law against liabilities that are incurred by the officers, directors and company secretary while executing the duties of their respective offices. Under the articles of association of the Registrant, the Registrant’s officers, directors and company secretary, however, will not be entitled to the indemnification by the Registrant if they incurred the liabilities through their own fraud, dishonesty or conscious, intentional or willful breach of the obligation to act honestly, lawfully and in good faith. In addition, the Irish Companies Acts prescribe that this indemnity only permits a company to pay the costs or discharge the liability of a director or the company secretary where judgment is given in any civil or criminal action in respect of such costs or liability, or where an Irish court grants relief because the director or company secretary acted honestly and reasonably and ought fairly to be excused. This restriction does not apply to executives who are not directors or the secretary of the Registrant. Any provision which seeks to indemnify a director or secretary of an Irish company over and above this shall be void under Irish law, whether contained in its articles of association or any contract between the director or company secretary and such company.

One of the Registrant’s subsidiaries has entered into a deed of indemnity as to each of the Registrants directors, company secretary and certain of its officers (as may be determined by the board of directors of the Registrants from time to time), on terms permitted by the articles of association.

The Registrant maintains insurance policies that indemnify its directors and officers against various liabilities arising under the Securities Act of 1933 and the Exchange Act that might be incurred by any director or officer in his or her capacity as such.

Item 7.  Exemption from Registration Claimed.

Not applicable.

Item 8.  Exhibits.

See Exhibit Index, which is incorporated into this Item by reference.

Item 9. Undertakings.

A.      The undersigned Registrant hereby undertakes that:

(1)         It will file, during any period in which offers or sales are being made, a post-effective amendment to this Registration Statement:

(i)                         To include any prospectus required by Section 10(a)(3) of the Securities Act;

(ii)                      To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the SEC pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20 percent change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective registration statement; and

(iii)                   To include any material information with respect to the plan of distribution not previously disclosed in the Registration Statement or any material change to such information in the Registration Statement.

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Provided, however, that paragraphs (A)(1)(i) and (A)(1)(ii) do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in periodic reports filed with or furnished to the SEC by the Registrant pursuant to Section 13 or Section 15(d) of the Exchange Act that are incorporated by reference in this Registration Statement.

(2)         For the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(3)         It will remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

B.                                    The undersigned Registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the Registrant’s annual report pursuant to Section 13(a) or Section 15(d) of the Exchange Act (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to Section 15(d) of the Exchange Act) that is incorporated by reference in the Registration Statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

C.                                    Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer or controlling person of the Registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Cupertino, State of California, on this 7th of October, 2015.

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SIGNATURES AND POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below hereby constitutes and appoints Stephen J. Luczo, Patrick J. O’Malley, and Regan MacPherson, and each of them, as his true and lawful attorneys-in-fact and agents, with power to act with or without the others and with full power of substitution and resubstitution, to sign and execute on behalf of the undersigned any amendment or amendments to the Registration Statement on Form S-8; and each of the undersigned hereby ratifies and confirms all that said attorneys and agents and each of them shall do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

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EXHIBIT INDEX

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Exhibit 5.1

Earlsfort Centre, Earlsfort Terrace, Dublin 2, Ireland | tel: +353 1 618 0000 | fax: +353 1 618 0618 | dx: 27 dublin | email: dublin@arthurcox.com

6 October 2015

To:                             Board of Directors

Seagate Technology public limited company

38/39 Fitzwilliam Square

Dublin 2

Ireland

Re:                             Seagate Technology plc

Form S-8 Registration Statement

Dear Sirs,

1.                                      Basis of Opinion

1.1                               We act as Irish counsel to Seagate Technology plc, registered number 480010, a public company limited by shares, incorporated under the laws of Ireland, with its registered office at 38/39 Fitzwilliam Square, Dublin 2 (the “Company”), in connection with the registration statement on Form S-8 to be filed with the United States Securities and Exchange Commission (the “SEC”) on the date hereof (the “Registration Statement”) under the Securities Act of 1933, as amended (the “Securities Act”), with respect to up to 1,973,638 ordinary shares with nominal value US$0.00001 per share of the Company (the “Shares”) that may be issued under the Dot Hill Systems Corp. 2009 Equity Incentive Plan (the “Plan”), as assumed by the Company pursuant to an acquisition agreement entered into between: (i) Seagate HDD Cayman; (ii) Denali Acquisition Sub Corp.; and (iii) Dot Hill Systems Corp dated 18 August 2015 (the “Acquisition Agreement”).

1.2                               This Opinion is confined to and given in all respects on the basis of the laws of Ireland in force as at the date hereof as currently applied by the courts of Ireland. We have made no investigations of and we express no opinion as to the laws of any other jurisdiction or the effect thereof. In particular, we express no opinion on the laws of the European Union as they affect any jurisdiction other than Ireland. We have assumed without investigation that insofar as the laws of any jurisdiction other than Ireland are relevant, such laws do not prohibit and are not inconsistent with any of the obligations or rights expressed in the Plan Documents (as defined in the Schedule) or the transactions contemplated thereby.

1.3                               This Opinion is also strictly confined to:

(a)                                 the matters expressly stated herein and is not to be read as extending by implication or otherwise to any other matter;

(b)                                 the Plan Documents (and no other documents whatsoever) and the Searches listed at paragraph 1.7 below,

and is subject to the assumptions and qualifications set out below.

1.4                               We express no opinion, and make no representation or warranty, as to any matter of fact or in respect of any documents which may exist in relation to the Plan or the Shares other than the Plan Documents.

1.5                               In giving this Opinion, we have relied upon the Corporate Certificate (as defined in the Schedule to this Opinion) and the Searches (as defined below) and we give this Opinion expressly on the terms that no further investigation or diligence in respect of any matter referred to in the Corporate Certificate or the Searches is required of us.

1.6                               For the purpose of giving this Opinion, we have examined copies sent to us by email in pdf or other electronic format of the Plan Documents.

1.7                               For the purpose of giving this Opinion, we have caused to be made legal searches against the Company on 6 October 2015 (together the “Searches”):

(a)                                 on the file of the Company maintained by the Registrar of Companies in the Irish Companies Registration Office for mortgages, debentures or similar charges or notices thereof and for the appointment of any examiner, receiver or liquidator;

(b)                                 in the Judgments Office of the High Court for unsatisfied judgments, orders, decrees and the like for the twelve years immediately preceding the date of the search;

(c)                                  in the Central Office of the High Court for any petitions filed in respect of the Company; and

(d)                                 in the Central Office of the High Court for any proceedings filed by or against the Company in the five years immediately preceding the date of the search.

1.8                               This Opinion is governed by and is to be construed in accordance with the laws of Ireland (as interpreted by the courts of Ireland at the date hereof). This Opinion speaks only as of its date. We assume no obligation to update this Opinion at any time in the future or to advise you of any change in law, change in interpretation of law which may occur after the date of this Opinion.

2.                                      Opinion

Subject to the assumptions and qualifications set out in this Opinion and to any matters not disclosed to us, we are of the opinion that:

2.1                               The Company is a public company limited by shares, is duly incorporated and validly existing under the laws of Ireland and has the requisite corporate authority to issue the Shares.

2.2                               When the Shares have been issued (and, if required, paid for in cash) pursuant to and in accordance with the terms and conditions referred to or summarised in the applicable resolutions, the Acquisition Agreement and the Plan, the Shares will be validly issued, fully paid up and non-assessable (which term means when used herein that no further sums are required to be paid in by the holders thereof in connection with the issue of the Shares).

3.                                      Assumptions

For the purpose of giving this Opinion we assume the following, without any responsibility on our part if any assumption proves to have been untrue as we have not verified independently any assumption:

The Registration Statement and the Plan

3.1                               when filed with the SEC, the Registration Statement will not differ in any material respect from the drafts that we have examined;

3.2                               that Shares issued pursuant to any awards under the Plan will be paid up in consideration of the receipt by the Company prior to, or simultaneously with, the issue of such Shares of cash at least equal to the nominal value of such Shares and any premium required to be paid up on the Shares pursuant to their terms of issue and that where Shares are issued under the Plan without the requirement for the payment of cash consideration by or on behalf of the relevant beneficiary, then such shares shall either be fully paid up by the Company or one of its subsidiaries within the time permitted by Section 1027 of the Companies Act 2014 (the “Act”) (and, in the case of the Company or a subsidiary incorporated in Ireland, in a manner permitted by sections 82(6) and 1043(1) of the Act or issued for consideration as set out in Section 1028(2) of the Act;

3.3                               that the filing of the Registration Statement with the SEC has been authorised by all necessary actions under applicable laws other than Irish law;

3.4                               that the exercise of any option and rights granted under the Plan and the issue of Shares upon exercise of such options and rights (and the issue of the Shares in connection with any other awards granted under the Plan) will be conducted in accordance with the terms and procedures described in the Plan and the applicable award agreement or enrolment form;

3.5                               that the Company will comply with the reservation of Shares set forth in the Plan and adopted by the Board;

3.6                               that as at the time of the issuance of the Shares, such issuance shall not be in contravention or breach of any agreement, undertaking, arrangement, deed or covenant affecting the Company or to which the Company is a party or otherwise bound or subject;

Authenticity and bona fides

3.7                               the completeness and authenticity of all documents submitted to us as originals or copies of originals and (in the case of copies) conformity to the originals of copy documents and genuineness of all signatories, stamps and seals thereon;

3.8                               where incomplete Plan Documents have been submitted to us or signature pages only have been supplied to us for the purposes of issuing this Opinion, that the originals of such Plan Documents correspond in all respects with the last draft of the complete Plan Documents submitted to us;

3.9                               that the Plan Documents will be executed in a form and content having no material difference to the drafts provided to us, will be delivered by the parties thereto, and that the terms thereof will be observed and performed by the parties thereto;

3.10                        that the copies produced to us of minutes of meetings and/or of resolutions correctly record the proceedings at such meetings and/or the subject matter which they purport to record and that any meetings referred to in such copies were duly convened, duly quorate and held, that those present at any such meetings were entitled to attend and vote at the meeting and acted bona fide throughout, that no further resolutions have been passed or corporate or other action taken which would or might alter the effectiveness thereof and that such resolutions have not been amended or rescinded and are in full force and effect;

3.11                        the Memorandum and Articles of Association of the Company amended on 30 October 2013 are the current Memorandum and Articles of Association of the Company, are up to date and have not been amended or superseded and that there are no other terms governing the Shares other than those set out in the Memorandum and Articles of Association of the Company;

Accuracy of searches and warranties

3.12                             the accuracy and completeness of the information disclosed in the Searches and that such information is accurate as of the date of this Opinion and has not since the time of such search been altered. It should be noted that (a) the matters disclosed in the Searches may not present a complete summary of the actual position on the matters we have caused searches to be conducted for, (b) the position reflected by the Searches may not be fully up-to-date and (c) searches at the Irish Companies Registration Office do not necessarily reveal whether or not a prior charge has been created or a resolution has been passed or a petition presented or any other action taken for the winding-up of, or the appointment of a receiver or an examiner to, the Company or its assets and, accordingly, it is assumed that the Searches correctly reflect that (i) no receiver, liquidator or examiner or other similar officer has been appointed in relation to the Company or any of its assets or undertakings; (ii) no petition for the making or a winding-up order or the appointment of an examiner or any similar officer has been presented in relation to the Company; (iii) no insolvency proceedings have been opened or been requested to be opened in relation to the Company; and (iv) the Company is as at the date of this Opinion able to pay its debts as they fall due within the meaning of section 570 of the Act and section 509 of the Act;

3.13                             the truth, completeness and accuracy of all representations and statements as to factual matters contained in the Plan Documents; and

Commercial Benefit

3.14                             that the Plan Documents have been entered into for bona fide commercial purposes, on arm’s length terms and for the benefit of each party thereto and are in those parties’ respective commercial interest and for their respective corporate benefit.

4.                                           Disclosure

This Opinion is addressed to you in connection with the registration of the Shares with the SEC. We hereby consent to the inclusion of this Opinion as an exhibit to the Registration Statement to be filed with the SEC and any amendments thereto. In giving this consent, we do not thereby admit that we are in a category of person whose consent is required under Section 7 of the Securities Act.

SCHEDULE

Plan Documents

1.                                 A copy of the Registration Statement to be filed by the Company with the SEC;

2.                                 A copy of the Plan;

3.                                 A copy of the Acquisition Agreement;

4.                                 A copy of the resolutions of the board of directors of the Company dated 21 July 2015;

5.                                 A copy of the resolutions of the Finance Committee of the board of directors of the Company dated 18 August 2015;

6.                                 A copy of the shareholders’ resolution adopting the Memorandum and Articles of Association of the Company dated 30 October 2013;

7.                                 A corporate certificate of the Company dated 6 October 2015 (the “Corporate Certificate”);

8.                                 A copy of the Memorandum and Articles of Association of the Company in the form adopted by resolution of the shareholders of the Company on 30 October 2013;

9.                                 A copy of the Certificate of Incorporation of the Company dated 22 January 2010;

10.                          A copy of the Certificate of Incorporation of Change of Name of the Company dated 22 February 2010; and

11.                          Letter of Status from the Irish Companies Registration Office dated 6 October 2015.

Exhibit 23.2

Consent of Independent Registered Public Accounting Firm

We consent to the incorporation by reference in this Registration Statement (Form S-8) pertaining to the Dot Hill Systems Corp. 2009 Equity Incentive Plan of our reports dated August 11, 2015, with respect to the consolidated financial statements of Seagate Technology plc and the effectiveness of internal control over financial reporting of Seagate Technology plc included in its Annual Report (Form 10-K) for the year ended July 3, 2015, filed with the Securities and Exchange Commission.

/s/ Ernst & Young LLP

San Jose, California

October 6, 2015