SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

[Rule 13d-101]

INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT

TO § 240.13d-1(a) AND AMENDMENTS THERETO FILED PURSUANT TO

§ 240.13d-1(a)

(Amendment No. 6)*

SPRINT CORPORATION

(Name of Issuer)

Common Stock, par value $0.01 per share

(Title of Class of Securities)

85207 U 10 5

(CUSIP Number)

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

September 16, 2013

(Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box: ¨

NOTE: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See §240.13d-7 for other parties to whom copies are to be sent.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (the “Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

(Continued on following pages)

EXPLANATORY NOTE

This Amendment No. 6 (this “Schedule 13D”) is being jointly filed on behalf of SoftBank Corp., a Japanese kabushiki kaisha (“SoftBank”), Starburst I, Inc., a Delaware corporation and wholly owned subsidiary of SoftBank (“Starburst I”) and Galaxy Investment Holdings, Inc., a Delaware corporation and wholly owned subsidiary of SoftBank (“Galaxy”, and together with SoftBank and Starburst I, the “Reporting Persons”, and each a “Reporting Person”) with respect to Sprint Corporation, a Delaware corporation (referred to herein as “New Sprint” or the “Issuer”). This Schedule 13D amends and restates the Schedule 13D filed by SoftBank, Starburst I, New Sprint and Starburst III, Inc., a Kansas corporation (“Merger Sub”) on October 25, 2012, as amended on April 22, 2013 and June 11, 2013, as amended and restated on July 12, 2013, and as amended on August 6, 2013 and August 27, 2013 (as amended and/or restated from time to time, the “Original 13D”), which relates to the common stock of New Sprint, par value $0.01 per share (the “New Sprint Common Stock”).

In connection with the completion of the Merger, as defined in the Agreement and Plan of Merger, dated October 15, 2012, by and among Sprint Nextel Corporation (“Sprint Nextel”), SoftBank, Starburst I, New Sprint, and Merger Sub, as amended on November 29, 2012, April 12, 2013 and June 10, 2013 (as amended, the “Merger Agreement”, which is incorporated by reference from Exhibits 99.2 through 99.5 to this Schedule 13D), Merger Sub was merged into Sprint Nextel, New Sprint became the parent company of Sprint Nextel, with Sprint Nextel becoming its wholly owned subsidiary, and Sprint Nextel changed its name to “Sprint Communications, Inc.” In connection with the Merger and by operation of Rule 12g-3(a) promulgated under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), New Sprint is the successor issuer to Sprint Nextel and has succeeded to the attributes of Sprint Nextel, including Sprint Nextel’s Securities and Exchange Commission (the “Commission”) file number (001-04721). The New Sprint Common Stock is deemed to be registered under Section 12(b) of the Exchange Act, and New Sprint is subject to the informational requirements of the Exchange Act, and the rules and regulations promulgated thereunder, and files reports and other information with the Commission using the Commission file number previously used by Sprint Nextel.

This Schedule 13D is being filed to reflect purchases of New Sprint Common Stock by Galaxy (i) pursuant to a Rule 10b-18 Purchase Agreement (the “Rule 10b-18 Purchase Agreement”) entered into by and between Galaxy and J.P. Morgan Securities LLC (“JPMS”) on August 1, 2013, which is incorporated by reference herein from Exhibit 99.8 (such purchases, the “Rule 10b-18 Purchases”) and (ii) in compliance with Rule 10b-18 of the Exchange Act and pursuant to a written plan under Rule 10b5-1 of the Exchange Act (the “Rule 10b5-1 Plan”) entered into by and between Galaxy and JPMS on August 30, 2013, which is attached hereto as Exhibit 99.12 and is incorporated by reference herein (such purchases, the “Rule 10b5-1 Purchases”, and together with the Rule 10b-18 Purchases, the “Galaxy Purchases”). Pursuant to the Rule 10b-18 Purchase Agreement and Rule 10b5-1 Plan, between August 1, 2013 and September 16, 2013, Galaxy, through JPMS, acquired approximately 2% of the outstanding shares of New Sprint Common Stock. As of September 17, 2013, the Rule 10b-18 Purchase Agreement and the Rule 10b5-1 Plan are no longer in effect. The Galaxy Purchases were made to increase SoftBank’s beneficial ownership in New Sprint to approximately 80% of the outstanding shares of New Sprint Common Stock (not including the shares of New Sprint Common Stock underlying the Warrant, as defined below). As of September 16, 2013, exclusive of any shares of New Sprint Common Stock underlying the Warrant, SoftBank may be deemed to beneficially own approximately 80% of the outstanding shares of New Sprint Common Stock, based on the outstanding New Sprint Common Stock as set forth in New Sprint’s Quarterly Report on Form 10-Q, filed with the Commission on August 5, 2013.

This Schedule 13D amends and restates the Original 13D in its entirety.

Item 1. Security and Issuer.

The class of equity securities to which this Schedule 13D relates is the Common Stock of the Issuer. The address of the Issuer’s principal executive offices is 6200 Sprint Parkway, Overland Park, Kansas 66251.

Item 2. Identity and Background.

(a) through (f) This Schedule 13D is being jointly filed on behalf of SoftBank, Starburst I and Galaxy.

The New Sprint Common Stock reported on this Schedule 13D is owned directly by Starburst I and Galaxy, as described in Item 5 to this Schedule 13D. SoftBank is included as a Reporting Person solely because it is the sole owner of both Starburst I and Galaxy. Pursuant to (i) SoftBank’s ownership of Starburst I and Galaxy, (ii) the Merger Agreement, (iii) the issuance by New Sprint to Starburst I of the New Sprint Warrant, dated July 10, 2013 (the “Warrant”, a copy of which is incorporated by reference from Exhibit 99.6 to this Schedule 13D and incorporated by reference into this Item 2), (iv) the Galaxy Purchases (the New Sprint Common Stock acquired by Galaxy in the Galaxy Purchases, the “Galaxy Shares”) and (v) Rule 13d-5(b)(1) under the Exchange Act, SoftBank, Starburst I and Galaxy may be deemed to be a “group” and such “group” may be deemed to have acquired beneficial ownership for purposes of Section 13(d) of the Exchange Act, of all of the New Sprint Common Stock beneficially owned by such “group.” Starburst I expressly disclaims beneficial ownership with respect to the Galaxy Shares. Galaxy expressly disclaims beneficial ownership with respect to the shares of New Sprint Common Stock deemed to be beneficially owned by SoftBank and Starburst I, except to the extent of Galaxy’s direct pecuniary interest in the Galaxy Shares.

Item 3. Source and Amount of Funds or Other Consideration.

Starburst I directly owns the New Sprint Common Stock (or, in the case of the Warrant, may be deemed to beneficially own the shares of New Sprint Common Stock underlying the Warrant (the “Warrant Shares”)), pursuant to (i) a reclassification exempt under

Rule 16b-7 under the Exchange Act, in which New Sprint Class B Common Stock, par value $0.01 per share, held by Starburst I was reclassified into 3,076,525,523 shares of New Sprint Common Stock (the “Reclassification”) and (ii) the issuance by New Sprint to Starburst I of the Warrant, which is subject to anti-dilution adjustment, as described in the Warrant. The New Sprint Common Stock held by Starburst I following the Reclassification and the Warrant Shares are referred to together in this Schedule 13D as the “Starburst I Shares.”

SoftBank initially financed the acquisition of the Starburst I Shares through a combination of borrowings under a bridge loan agreement dated December 18, 2012 with Mizuho Corporate Bank, Ltd. (now Mizuho Bank, Ltd.), Sumitomo Mitsui Banking Corporation, The Bank of Tokyo-Mitsubishi UFJ, Ltd. and Deutsche Bank AG, Tokyo Branch; proceeds from a global offering of senior U.S. dollar and euro notes on April 23, 2013; and proceeds from Japanese domestic offerings of yen-denominated unsecured corporate bonds on March 1, 2013, March 12, 2013 and June 20, 2013.

Pursuant to the Merger Agreement, no additional consideration was payable in connection with the issuance to Starburst I of the Warrant to purchase 54,579,924 shares of New Sprint Common Stock at a price of $5.25 per share. The Warrant is exercisable at any time until July 10, 2018.

Between August 1, 2013 and September 16, 2013, Galaxy purchased 74,559,641 shares of New Sprint Common Stock pursuant to the Rule 10b-18 Purchase Agreement and the Rule 10b5-1 Plan, for an aggregate purchase price of $498,508,805.88, exclusive of any fees, commissions or other expenses. Galaxy directly beneficially owns the Galaxy Shares. Galaxy’s acquisition of the Galaxy Shares was financed from SoftBank’s general working capital.

Pursuant to SoftBank’s ownership of Starburst I and Galaxy, SoftBank may be deemed to beneficially own the Starburst I Shares and the Galaxy Shares.

Item 4. Purpose of Transaction.

Purpose of the Transaction

SoftBank may be deemed a beneficial owner of the Starburst I Shares and the Galaxy Shares as described in Item 3 to this Schedule 13D. The Merger is intended to make Sprint a stronger, more competitive company that will deliver significant benefits to U.S. consumers based on SoftBank’s expertise in the deployment of next-generation wireless networks and track record of success in taking share in mature markets from larger telecommunications competitors.

Starburst I directly owns the New Sprint Common Stock as a result of the Reclassification, and may be deemed to beneficially own the Warrant Shares.

On August 1, 2013, Galaxy commenced making the Galaxy Purchases. As of September 16, 2013, as a result of the Galaxy Purchases, Galaxy had directly acquired 74,559,641 shares of New Sprint Common Stock, or approximately 1.90% of the outstanding shares of New Sprint Common Stock, based on the outstanding New Sprint Common Stock as set forth in New Sprint’s Quarterly Report on Form 10-Q, filed with the Commission on August 5, 2013. As of September 17, 2013, the Rule 10b-18 Purchase Agreement and the Rule 10b5-1 Plan are no longer in effect.

Plans or Proposals

The Reporting Persons, as stockholders in New Sprint, intend to review their investment in New Sprint and have discussions with representatives of New Sprint and/or other stockholders of New Sprint from time to time and, as a result thereof, may at any time and from time to time determine to take any available course of action and may take any steps to implement any such course of action. Such review, discussions, actions or steps may involve one or more of the types of transactions specified in clauses (a) through (j) of Item 4 of this Schedule 13D, including purchase or sale of New Sprint Common Stock, business combination or other extraordinary corporate transactions, sales or purchases of material assets, changes in the board of directors or management of New Sprint, changes to New Sprint’s business or corporate structure, shared service agreements, collaborations, joint ventures and other business arrangements between or involving SoftBank and New Sprint. Any action or actions the Reporting Persons might undertake in respect of the New Sprint Common Stock will be dependent upon the Reporting Persons’ review of numerous factors, including, among other things, the price level and liquidity of the New Sprint Common Stock; general market and economic conditions; ongoing evaluation of New Sprint’s business, financial condition, operations, prospects and strategic alternatives; the relative attractiveness of alternative business and investment opportunities; tax considerations; and other factors and future developments. Notwithstanding anything to the contrary herein, the Reporting Persons specifically reserve the right to change their intentions with respect to any or all of such matters.

Item 5. Interest in Securities of the Issuer.

(a)-(b) As of September 16, 2013, each Reporting Person may be deemed to have beneficial ownership (within the meaning of Rule 13d-3 under the Exchange Act) and shared power to vote or direct the vote of up to the number of shares of New Sprint Common

Stock set forth in the table below and may be deemed to constitute a “group” under Section 13(d) of the Exchange Act as described in Item 2 of this Schedule 13D, which is incorporated herein by reference.

(c) The information contained in Items 3 and 4 to this Schedule 13D is herein incorporated by reference. In connection with the closing of the Merger, all Sprint Nextel common stock and options to acquire Sprint Nextel common stock held by directors and executive officers of Sprint Nextel (immediately prior to the consummation of the Merger) were exchanged for Merger Consideration (as defined in the Merger Agreement) or options to purchase New Sprint Common Stock pursuant to the terms of the Merger Agreement.

The weighted average price per share, exclusive of any fees, commissions or other expenses for the Galaxy Purchases made between August 1, 2013 and September 16, 2013 are as set forth in the following table:

The Reporting Persons undertake to provide New Sprint, any stockholder of New Sprint, or the Staff of the Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in this Item 5(c) to this Schedule 13D.

Except as set forth above or incorporated herein, none of (i) the Reporting Persons and, (ii) to the Reporting Persons’ knowledge, the persons set forth on Appendix A-1, A-2 or A-3 of this Schedule 13D has effected any transaction in New Sprint Common Stock during the past 60 days.

(d) To the best knowledge of the Reporting Persons, no other person has the right to receive or the power to direct the receipt of dividends from, or the proceeds of the sale of, the securities that are the subject of this Schedule 13D.

(e) Not applicable.

Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer.

As of September 17, 2013, the Rule 10b-18 Purchase Agreement and the Rule 10b5-1 Plan, copies of which are incorporated by reference from Exhibits 99.8 and 99.12, respectively, are no longer in effect.

The Warrant, a copy of which is incorporated by reference from Exhibit 99.6 to this Schedule 13D, is incorporated by reference into this Item 6.

Pursuant to the terms of the Merger Agreement, during the 24 months immediately following the consummation of the Merger, the board of directors of New Sprint will consist of 10 members, as follows:

As of the date hereof, Masayoshi Son, founder, Chairman and CEO of SoftBank, Ronald D. Fisher, President of Starburst I, Daniel R. Hesse, Chief Executive Officer of New Sprint, Admiral Michael G. Mullen USN (ret), Security Director of New Sprint, Frank Ianna, Robert R. Bennett, Gordon M. Bethune and Sara Martinez Tucker are members of the New Sprint board of directors. The New Sprint board of directors has determined that each of Adm. Mullen and Messrs. Bennett, Bethune and Ianna and Ms. Tucker are “Independent Directors.” The other vacancies on the New Sprint board of directors will be filled by the board of directors of New Sprint.

In addition, during the 12 months immediately following the 24 month period described above, the board of directors of New Sprint will consist of 10 members, determined as follows:

Each director of New Sprint will remain in office until his or her earlier resignation or his or her successors are elected in accordance with the bylaws of New Sprint.

At all times following the periods described above until such time as the combined voting interest of SoftBank and its controlled affiliates in New Sprint falls below 50% and remains below 50% for 90 consecutive days, the New Sprint board of directors will include not fewer than three (or such greater number as may be required by applicable law or listing rules) individuals who qualify as “Independent Directors.” Thereafter, unless and until the combined voting interest of SoftBank and its controlled affiliates in New Sprint remains below 10% for 90 consecutive days, the New Sprint board of directors will include a number of individuals nominated

by SoftBank or its controlled affiliate that is proportional to the combined voting interest of SoftBank and its controlled affiliates in New Sprint, rounded up to the nearest whole number.

The foregoing summary of certain provisions of the Merger Agreement is not intended to be complete and is qualified in its entirety by reference to the full text of the Merger Agreement, which is incorporated by reference from Exhibits 99.2 through 99.5 to this Schedule 13D, and is incorporated by reference into Item 4 of this Schedule 13D.

Pursuant to the Amended and Restated Certificate of Incorporation of New Sprint, in the event that SoftBank’s (including through its controlled affiliates) voting interest in New Sprint exceeds 85%, either SoftBank or its controlled affiliate must commence a tender offer to acquire all shares of New Sprint Common Stock not owned by SoftBank (or its controlled affiliates), subject to certain conditions. Alternately, in such an event, SoftBank may, but is not obligated to, cause New Sprint to effect a merger or other business combination to acquire the New Sprint Common Stock not owned by SoftBank or its controlled affiliates. A copy of the Amended and Restated Certificate of Incorporation of New Sprint is incorporated by reference from Exhibit 99.7 to this Schedule 13D and incorporated by reference into this Item 6.

Item 7. Material to be Filed as Exhibits.

SIGNATURES

After reasonable inquiry and to the best of our knowledge and belief, the undersigned certify that the information set forth in this statement is true, complete and correct.

Dated: September 18, 2013

Appendix A-1

EXECUTIVE OFFICERS AND DIRECTORS

OF

SOFTBANK CORP.

Set forth below is a list of each executive officer and director of SoftBank Corp. setting forth the business address and present principal occupation or employment (and the name and address of any corporation or organization in which such employment is conducted) of each person.

Appendix A-2

EXECUTIVE OFFICERS AND DIRECTORS

OF

STARBURST I, INC.

Set forth below is a list of each executive officer and director of Starburst I, Inc. setting forth the business address and present principal occupation or employment (and the name and address of any corporation or organization in which such employment is conducted) of each person. Unless otherwise indicated, each individual is a United States citizen.

Appendix A-3

EXECUTIVE OFFICERS AND DIRECTORS

OF

GALAXY INVESTMENT HOLDINGS, INC.

Set forth below is a list of each executive officer and director of Galaxy Investment Holdings, Inc. setting forth the business address and present principal occupation or employment (and the name and address of any corporation or organization in which such employment is conducted) of each person.

EXHIBIT INDEX

Exhibit 99.12

10b5-1/10b-18 PURCHASE PLAN AGREEMENT

August 30, 2013

Galaxy Investment Holdings, Inc.

1209 Orange Street

Wilmington, DE 19801

This letter agreement (this “Letter Agreement”) confirms the terms and conditions under which Galaxy Investment Holdings, Inc. (the “Purchaser”) hereby establishes a plan (the “Plan”) to purchase shares of common stock, par value $0.01 (the “Securities”), of Sprint Corporation (the “Issuer”), and under which J.P. Morgan Securities LLC (“JPMS”) will act as its exclusive agent to execute the Plan.

(a) On each Trading Day during the Plan Period on which no Market Disruption Event (as defined below) occurs, JPMS shall use commercially reasonable efforts to purchase as agent for the Purchaser and for the account of the Purchaser the lesser of (i) the maximum number of Securities that the Purchaser could purchase on such Trading Day in accordance with the volume condition set forth in Rule 10b-18 and (ii) the number of Securities that JPMS is able, subject to market conditions and principles of best execution, to purchase as agent for the Purchaser and for the account of the Purchaser on such Trading Day using commercially reasonable means in accordance with the Plan guidelines set forth in Annex A hereto. JPMS may purchase Securities on the Principal Market, any national securities exchange, in the over-the-counter market, on an automated trading system or otherwise. Any numbers of Securities to be purchased (and any corresponding purchase price limits or ranges) set forth in Annex A shall be adjusted automatically on a proportionate basis to take into account any stock split, reverse stock split or stock dividend with respect to the Securities or any change in capitalization with respect to the Issuer or any similar event that occurs during the term of this Letter Agreement, as determined by JPMS in good faith and a commercially reasonable manner.

A “Trading Day” is any day during the Plan Period that the Principal Market is open for business and the Securities trade regular way on the Principal Market.

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“Market Disruption Event” means that (i) there occurs any material (as reasonably determined by JPMS) suspension of or limitation on trading by the Principal Market, (ii) there occurs any event that materially (as reasonably determined by JPMS) disrupts or impairs the ability of market participants in general to effect transactions in or obtain market values for the Securities or futures or options contracts on the Securities or (iii) the Principal Market closes prior to its scheduled closing time for such trading day.

(b) In the event that JPMS, in its discretion, determines that it is appropriate with regard to any legal, regulatory or self-regulatory requirements or related internal policies and procedures (whether or not such requirements, policies or procedures are imposed by law or have been voluntarily adopted by JPMS) for JPMS to refrain from purchasing Securities or to purchase fewer than the number of Securities otherwise specified in the instructions provided by the Purchaser on any day, then JPMS may, in its sole discretion, elect that the number of Securities purchased shall be reduced for such day to an amount determined by JPMS in its discretion.

(c) Any Securities purchased pursuant to the Plan shall be purchased under ordinary principles of best execution at the then-prevailing market price. Subject to the terms of the Plan as set forth herein (including Annex A hereto), JPMS shall have full discretion with respect to the execution of all purchases, and the Purchaser acknowledges and agrees that the Purchaser does not have, and shall not attempt to exercise, any influence over how, when or whether purchases of Securities are affected pursuant to the Plan. The Purchaser acknowledges and agrees that, in purchasing Securities pursuant to the Plan, JPMS will be an independent contractor and will not be acting as the Purchaser’s trustee or fiduciary or in any similar capacity. JPMS agrees that no person who exercises influence, directly or indirectly, on its behalf in effecting purchases of Securities pursuant to this Letter Agreement may do so while aware of material, non-public information relating to the Securities or the Issuer.

(a) This Letter Agreement and the transactions contemplated herein have been duly authorized by the Purchaser and have been reviewed, to the extent required, pursuant to or under any and all applicable policies and procedures of the Issuer applicable to purchases of Securities by its “affiliated purchasers”; this Letter Agreement is the valid and binding agreement of the Purchaser, enforceable in accordance with its terms, except as the enforcement thereof may be limited by bankruptcy, insolvency, reorganization, moratorium or other similar laws relating to or affecting the rights and remedies of creditors or by general equitable principles and except as rights to indemnification as may be limited by applicable law; performance of the transactions contemplated herein will not violate any law, rule, regulation, order, judgment or decree applicable to the Purchaser or conflict with or result in a breach of or constitute a default under any agreement or instrument to which the Purchaser is a party or by which it or any of its property is bound or its certificate of incorporation or by-laws; and no governmental, administrative or official consent, approval or authorization is required for performance of the transactions contemplated herein.

(b) As of the date of this Letter Agreement, the Purchaser is not aware of any material nonpublic information concerning the Securities or the business, operations or prospects of the Issuer.

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(c) The Purchaser is engaging JPMS and entering into this Letter Agreement and the Plan in good faith and not as part of a plan or scheme to evade compliance with the federal securities laws, including, without limitation, Rule 10b-5 under the Exchange Act. Until this Letter Agreement is terminated, the Purchaser agrees not to enter into or alter any corresponding or hedging transaction or position with respect to the Securities.

(d) The Purchaser is not entering into this Letter Agreement to create actual or apparent trading activity in the Securities (or any security convertible into or exchangeable for the Securities) or to raise or depress the price of the Securities (or any security convertible into or exchangeable for the Securities) for the purpose of inducing others to buy or sell Securities, and will not engage in any other securities or derivative transaction to such ends.

(e) During the term of this Letter Agreement, neither the Purchaser nor its officers or employees shall, directly or indirectly, disclose to any person at JPMS effecting purchases under the Plan any material nonpublic information regarding the Issuer or the Securities or any information regarding the Issuer or the Securities that could reasonably be expected to influence the execution of the Plan.

(f) The Purchaser acknowledges that JPMS is a “financial institution” and “financial participant” within the meaning of Sections 101(22) and 101(22A), respectively, of Title 11 of the United States Code (the “Bankruptcy Code”). The parties hereto further agree and acknowledge that each transaction under this Letter Agreement is intended to be a “securities contract” as defined in Section 741(7) of the Bankruptcy Code and each payment or delivery of cash, Securities or other property or assets hereunder is a “settlement payment” within the meaning of Section 741(8) of the Bankruptcy Code, and the parties hereto are to be entitled to the protections afforded by, among other Sections, Sections 362(b)(6), 362(b)(27), 362(o), 546(e), 546(j), 555 and 561 of the Bankruptcy Code.

(g) Prior to 8:00 a.m., New York City time on the Start Date, the Purchaser shall provide to JPMS all information, other than publicly reported trading volumes, as may be reasonably requested by JPMS that is necessary for JPMS to calculate the maximum number of Securities that may be purchased as of the Start Date in accordance with the volume condition set forth in Rule 10b-18, and JPMS shall be entitled to rely on such information so provided.

(h) The Purchaser shall not, and shall cause SoftBank Corp. and its controlled subsidiaries and affiliates not to, take any action that would cause Regulation M under the Exchange Act (“Regulation M”) to be applicable to any purchases of Securities, or any security for which the Securities are a reference security (as defined in Regulation M), by the Purchaser during the Plan Period. The Purchaser agrees that it will elect to terminate this Letter Agreement pursuant to Paragraph 10 should Sprint Corporation, Yahoo Japan Corporation or their respective subsidiaries take any action contemplated in this Section during the Plan Period.

(i) The Purchaser shall be solely responsible for compliance with all statutes, rules and regulations applicable to the Purchaser and the transactions contemplated hereby, including, without limitation, reporting and filing requirements. The Purchaser acknowledges and agrees that it is not relying, and has not relied, upon JPMS or any affiliate of JPMS with respect to the legal, accounting, tax or other implications of the Plan and the transactions contemplated thereby and that it has conducted its own analyses of the legal, accounting, tax and other implications hereof. JPMS has made no representation and has no obligation with respect to whether the Plan or the transactions contemplated thereunder qualify for the safe harbor provided by Rule 10b-18 or the affirmative defense provided by Rule 10b5-1.

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J.P. Morgan Securities LLC

383 Madison Avenue, 5^th Floor

New York, NY 10179

Attention: James F. Smith

Telephone: (212) 622-2922    Fax: (917) 464-8885

or at such other address as may from time to time be designated by notice to the Purchaser in writing; and

SoftBank Capital

38 Glen Avenue

Newtown Center, MA 02549

Attn: Josh Lubov

Email: josh_lubov@softbank.com

Telephone: (617) 558-6715    Fax: (617) 928-9302

or at such other address as may from time to time be designated by notice to JPMS in writing.

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If the foregoing correctly sets forth our agreement, please sign the form of acceptance below.

Annex A

The above share percentages for maximum daily repurchase limits are to be followed on a trade-by-trade basis. If during the day the stock price increases to a higher price category, as set forth above, purchases must cease, if the maximum percentage for that limit price has already been purchased. If during the trading day the stock price falls to a lower price category, as set forth above, purchases may resume, subject to the maximum daily amount for the lower price, which shall be aggregated with any prior purchases for such trading day. Notwithstanding anything in this Annex A to the contrary, in all circumstances JPMS will make such purchases pursuant to the safe harbor provided by Rule 10b-18.

A-1