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-2(a)

(Amendment No. 9)*

Clearwire Corporation

(Name of Issuer)

Class A Common Stock

(Title of Class of Securities)

18538Q105

(CUSIP Number)

David K. Schumacher

General Counsel

Crest Financial Limited

JP Morgan Chase Tower

600 Travis, Suite 6800

Houston, TX 77002

Tel: (713) 222 6900

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

Copies to:

Stephen M. Gill

Kai Haakon E. Liekefett

Vinson & Elkins LLP

First City Tower

1001 Fannin Street, Suite 2500

Houston, TX 77002

Tel: (713) 758 2222

April 24, 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)

This Amendment No. 9 (this “Amendment”) amends and supplements the Statement on Schedule 13D (the “Schedule 13D”) of Crest Financial Limited (“CFL”), Crest Investment Company (“CIC”), the Jamal and Rania Daniel Revocable Trust (the “Jamal and Rania Daniel Trust”), Mr. Jamal Daniel, Mrs. Rania Daniel, DTN LNG, LLC (“DTN LNG”), DTN Investments, LLC (“DTN Investments”), the Daria Daniel 2003 Trust (the “Daria Daniel Trust”), the Thalia Daniel 2003 Trust (the “Thalia Daniel Trust”), the Naia Daniel 2003 Trust (the “Naia Daniel Trust”), Mr. John M. Howland, Mr. Eric E. Stoerr, the Halim Daniel 2012 Trust (the “Halim Daniel Trust”), Mr. Michael Wheaton, solely in his capacity as trustee of the Halim Daniel Trust, Mr. Halim Daniel, Uniteg Holding SA (“Uniteg”) and Crest Switzerland, LLC (“Crest Switzerland” and, together with CFL, CIC, the Jamal and Rania Daniel Trust, Mr. Jamal Daniel, Mrs. Daniel, DTN LNG, DTN Investments, the Daria Daniel Trust, the Thalia Daniel Trust, the Naia Daniel Trust, Mr. Howland, Mr. Stoerr, the Halim Daniel Trust, Mr. Wheaton, solely in his capacity as trustee of the Halim Daniel Trust, Mr. Halim Daniel, Uniteg and Crest Switzerland, the “Reporting Persons”) that was filed in respect of Clearwire Corporation (the “Issuer”) on June 1, 2012 and amended by Amendment No. 1 filed on November 7, 2012 (“Amendment No. 1”), Amendment No. 2 filed on December 18, 2012 (“Amendment No. 2”), Amendment No. 3 filed on March 13, 2013 (“Amendment No. 3”), Amendment No. 4 filed on March 20, 2013 (“Amendment No. 4”), Amendment No. 5 filed on April 4, 2013 (“Amendment No. 5”), Amendment No. 6 filed on April 9, 2013 (“Amendment No. 6”), Amendment No. 7 filed on April 11, 2013 (“Amendment No. 7”) and Amendment No. 8 filed on April 23, 2013 (“Amendment No. 8”).

Item 4 of the Schedule 13D is hereby amended and supplemented by adding the following paragraphs after the first paragraph thereof:

On April 24, 2013, CFL and CIC (collectively, the “Participants”) filed with the Securities and Exchange Commission (the “SEC”) a revised preliminary proxy statement and accompanying proxy card relating to Participants’ intention to solicit proxies from the stockholders of the Issuer in connection with a special meeting of such stockholders to be held to vote upon the proposed transaction between the Issuer and Sprint-Nextel Corporation and issued a press release relating thereto (the “Press Release”), a copy of which is attached hereto as Exhibit 2 and is incorporated herein by reference.

Item 6 of the Schedule 13D is hereby amended and restated in its entirety as follows:

Other than Asset Purchase Agreement as described in Item 3 hereof (which has been fully performed by the parties thereto in 2004), the Joint Filing Agreement attached hereto as Exhibit 1, the Press Release attached hereto as Exhibit 2, the Power of Attorney for the Jamal and Rania Daniel Trust attached hereto as Exhibit 3, the Power of Attorney for Jamal Daniel attached hereto as Exhibit 4, the Power of Attorney for Rania Daniel attached hereto as Exhibit 5, the Power of Attorney for Eric E. Stoerr attached hereto as Exhibit 6, the Power of Attorney for the Halim Daniel Trust attached hereto as Exhibit 7, the Power of Attorney for Halim Daniel attached hereto as Exhibit 8, the Power of Attorney for Michael Wheaton attached hereto as Exhibit 9, the Power of Attorney for Uniteg attached hereto as Exhibit 10, the Board Letter attached to Amendment No. 8 as Exhibit 2, the April 23 Press Release attached to Amendment No. 8 as Exhibit 3, the April 22 Press Release attached to Amendment No. 8 as Exhibit 4, the FCC Letter attached to Amendment No. 8 as Exhibit 5, the Press Release attached to Amendment No. 7 as Exhibit 2, the Press Release attached to Amendment No. 6 as Exhibit 2, the FCC Letter attached to Amendment No. 6 as Exhibit 3, the Letter to the Board attached to Amendment No. 5 as Exhibit 2, the April 3 Press Release attached to Amendment No. 5 as Exhibit 3, the Demand Letter attached to Amendment No. 4 as Exhibit 2, the March 20 Press Release attached to Amendment No. 4 as Exhibit 3, the March 12 Press Release attached to Amendment No. 3 as Exhibit 2, the FCC Letter attached to Amendment No. 3 as Exhibit 3, the Press Release attached to Amendment No. 2 as Exhibit 2, the Stockholder Letter attached to Amendment No. 1 as Exhibit 2 and the Press Release attached to Amendment No. 1 as Exhibit 3, neither the Reporting Persons nor, to the best of the Reporting Persons’ knowledge, any person named on Schedule A hereto, has any contracts, arrangements, understandings or relationships (legal or otherwise) among the persons named in Item 2 and between such persons and any person with respect to any securities of the Issuer, including but not limited to, transfer or voting of any of the securities, finder’s fees, joint ventures, loan or option arrangements, puts or calls, guarantees of profits, division of profits or loss, or the giving or withholding of proxies.

The following documents are filed as exhibits:

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

Date: April 25, 2013

EXHIBIT INDEX

Exhibit 1

JOINT FILING AGREEMENT

In accordance with Rule 13d-1(k)(1) under the Securities Exchange Act of 1934, as amended, the persons named below agree to the joint filing on behalf of each of them of a statement on Schedule 13D (including amendments thereto) with respect to the Class A Common Stock of Clearwire Corporation and further agree that this Joint Filing Agreement be included as an Exhibit to such joint filings. In evidence thereof, the undersigned, being duly authorized, have executed this Joint Filing Agreement this 25^th day of April, 2013.

Exhibit 2

FOR IMMEDIATE RELEASE:

CONTACT: Jeffrey Birnbaum, (202) 661-6367, JBirnbaum@BGRPR.com

Crest Financial Files Revised Preliminary Proxy Statement

HOUSTON, April 24, 2013 – Crest Financial Limited, the largest minority stockholder of Clearwire Corporation (NASDAQ: CLWR), today filed with the Securities and Exchange Commission (SEC) a revised preliminary proxy statement regarding the proposed merger between Clearwire Corporation and Sprint Nextel Corporation. Once its proxy statement is declared effective by the SEC, Crest intends to wage a campaign to convince the Clearwire stockholders to vote against the proposed merger.

Crest has made a number of public statements, including through letters, press releases and filings with the Federal Communications Commission and the Delaware Court of Chancery, regarding its opposition to the Sprint-Clearwire merger. This process continued yesterday in a new letter to the Clearwire Board of Directors.

In the letter, Crest continued to express its strongly held belief that Clearwire should be left to realize the full value of its spectrum by implementing its multi-customer strategy as an independent company. Crest asserted that the market itself, as evidenced by the spectrum purchase offers from DISH Network and Verizon, demonstrates that this path is real. By contrast, Crest said that Clearwire’s threats of bankruptcy or debt default are not real. In Crest’s view, with a bidding war heating up for Clearwire’s valuable spectrum through the SoftBank and DISH offers for Sprint and the offers made directly to Clearwire for spectrum, none of the relevant players would hand control of Clearwire’s spectrum to Clearwire’s bondholders through a debt default or bankruptcy filing.

Crest’s letter provided a detailed statement about how Clearwire’s Board of Directors has not acted in the interests of the Clearwire stockholders other than Sprint. These include:

Crest also pointed out that it is Sprint, not Clearwire, that had to find a transaction partner to save it from its failing finances. While Sprint was starving for cash, overrun with debt, losing customers, and facing a very legitimate risk of bankruptcy, Clearwire had its valuable spectrum assets and the cash available to meet its build-out objectives. However, it was the Sprint Board, and not the Clearwire Board, that turned this situation into an advantage, Crest states in its letter.

Finally, Crest’s letter asks how the Clearwire Board could press ahead with a vote on the Sprint-Clearwire transaction when the fluid situation in the market leaves Clearwire’s stockholders with a lack of clarity about what they are voting for or against as well as what is the future of Clearwire’s majority stockholder, Sprint. Crest believes that the Clearwire Board is presenting the Clearwire stockholders with a choice: Take the inadequate offer from Sprint or allow Clearwire to continue on the independent path that Crest has described. Crest also asserts that the Clearwire Board should answer a number of questions so that the Clearwire stockholders can make an informed choice, including whether these market moves demonstrate that Clearwire’s spectrum is significantly more valuable than the value the Sprint offer attributes to it; and who will control Sprint, Clearwire’s majority stockholder, and what business plan will Sprint’s new majority stockholder implement to realize the full value of Clearwire’s spectrum.

Crest has hired the proxy-solicitation firm D. F. King & Co., Inc. to help it oppose the proposed Sprint-Clearwire merger. Crest has also filed a lawsuit in Delaware against Sprint, Clearwire, the directors of Clearwire, and others because Crest believes that the defendants breached their fiduciary duties by scheming to extract value from Clearwire at the expense of the minority stockholders. In addition, Crest has petitioned the Federal Communications Commission to block the proposed Softbank-Sprint and Sprint-Clearwire transactions because they would treat minority stockholders of Clearwire unfairly and the transactions would not be in the public’s best interest.

Crest’s revised preliminary proxy statement and its letter to the Board of Clearwire can be found at http://www.bancroftpllc.com/crest/.

About Crest Financial Limited

Crest Financial Limited is a limited partnership under the laws of the State of Texas. Its principal business is investing in securities.

Important Legal Information

CREST FINANCIAL LIMITED AND OTHER PERSONS MAY BE DEEMED TO BE PARTICIPANTS (THE “PARTICIPANTS”) IN A SOLICITATION OF PROXIES IN RESPECT OF THE PROPOSED MERGER OF CLEARWIRE WITH SPRINT NEXTEL CORPORATION. THE PARTICIPANTS HAVE FILED A PRELIMINARY PROXY STATEMENT WITH THE SECURITIES AND EXCHANGE COMMISSION (“SEC”). THE PRELIMINARY PROXY STATEMENT IS AVAILABLE AT NO CHARGE ON THE WEBSITE OF THE PARTICIPANTS’ PROXY SOLICITOR AT HTTP://WWW.DFKING.COM/CLWR AND ON THE SEC’S WEBSITE AT HTTP://WWW.SEC.GOV. THE PARTICIPANTS INTEND TO FILE WITH THE SEC A DEFINITIVE PROXY STATEMENT AND ACCOMPANYING PROXY CARD IN CONNECTION WITH SUCH PROXY SOLICITATION. WHEN COMPLETED, ANY SUCH DEFINITIVE PROXY STATEMENT AND PROXY CARD WILL BE FURNISHED TO SOME OR ALL OF THE STOCKHOLDERS OF THE ISSUER AND WILL, ALONG WITH OTHER RELEVANT DOCUMENTS, BE AVAILABLE AT NO CHARGE ON THE WEBSITE OF THE PARTICIPANTS’ PROXY SOLICITOR AT HTTP://WWW.DFKING.COM/CLWR AND ON THE SEC’S WEBSITE AT HTTP://WWW.SEC.GOV. IN ADDITION, THE PARTICIPANTS WILL PROVIDE COPIES OF THE DEFINITIVE PROXY STATEMENT AND ACCOMPANYING PROXY CARD (WHEN AVAILABLE) AT NO CHARGE UPON REQUEST. INFORMATION RELATING TO THE PARTICIPANTS IN SUCH PROXY SOLICITATION IS CONTAINED IN THE PRELIMINARY PROXY STATEMENT. STOCKHOLDERS OF THE ISSUER ARE ADVISED TO READ THE PRELIMINARY PROXY STATEMENT, WHICH IS AVAILABLE NOW, AND ANY DEFINITIVE PROXY STATEMENT AND OTHER DOCUMENTS FILED WITH THE SEC WHEN THEY BECOME AVAILABLE, BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION, INCLUDING ADDITIONAL INFORMATION RELATED TO THE PARTICIPANTS IN ANY SUCH SOLICITATION.

Forward-looking Statements

Certain statements contained herein are forward-looking statements including, but not limited to, statements that are predications of or indicate future events, trends, plans or objectives. Undue reliance should not be placed on such statements because, by their nature, they are subject to known and unknown risks and uncertainties. Forward-looking statements are not guarantees of future activities and are subject to many risks and uncertainties. Due to such risks and uncertainties, actual events may differ materially from those reflected or contemplated in such forward-looking statements. Forward-looking statements can be identified by the use of the future tense or other forward-looking words such as “believe,” “expect,” “anticipate,” “intend,” “plan,” “should,” “may,” “will,” believes,” “continue,” “strategy,” “position” or the negative of those terms or other variations of them or by comparable terminology.

Exhibit 3

POWER OF ATTORNEY

FOR EXECUTING SCHEDULE 13D AND SCHEDULE 13G

The undersigned hereby constitutes and appoints each of Pamela E. Powers and David K. Schumacher, with full power of substitution, as an undersigned’s true and lawful attorney-in-fact to:

The undersigned hereby grants to each attorney-in-fact full power and authority to do and perform all and every act requisite, necessary or proper to be done in the exercise of any of the rights and powers herein granted, as fully to all intents and purposes as the undersigned might or could do if personally present, with full power of substitution or revocation, hereby ratifying and confirming all that each attorney-in-fact shall lawfully do or cause to be done by virtue of this Power of Attorney and the rights and powers granted herein. The undersigned acknowledges that none of the attorneys-in-fact, in serving in such capacity at the request of the undersigned, is assuming any of the undersigned’s responsibilities to comply with Sections 13(d) or 13(g) of the Exchange Act.

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The undersigned agrees that each attorney-in-fact may rely entirely on information furnished orally or in writing by or at the direction of the undersigned to the attorney-in-fact. The undersigned also agrees to indemnify and hold harmless each attorney-in-fact against any losses, claims, damages or liabilities (or actions in these respects) that arise out of or are based upon any untrue statements or omissions of necessary facts in the information provided by or at the direction of the undersigned, or upon the lack of timeliness in the delivery of information by or at the direction of the undersigned, to the attorneys-in fact for purposes of executing, acknowledging, delivering or filing a Schedule 13D or Schedule 13G (including amendments thereto) and agrees to reimburse each attorney-in-fact on demand for any legal or other expenses reasonably incurred in connection with investigating or defending against any such loss, claim, damage, liability or action.

This Power of Attorney shall remain in full force and effect until the undersigned is no longer required to file a Schedule 13D or Schedule 13G (including amendments thereto) with respect to the undersigned’s holdings of and transactions in securities issued by Clearwire Corporation, unless earlier revoked by the undersigned in a signed writing delivered to the attorney-in-fact. This Power of Attorney does not revoke any other power of attorney that the undersigned has previously granted.

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IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be executed as of the date written below.

Exhibit 4

POWER OF ATTORNEY

FOR EXECUTING SCHEDULE 13D AND SCHEDULE 13G

The undersigned hereby constitutes and appoints each of Pamela E. Powers and David K. Schumacher, with full power of substitution, as an undersigned’s true and lawful attorney-in-fact to:

The undersigned hereby grants to each attorney-in-fact full power and authority to do and perform all and every act requisite, necessary or proper to be done in the exercise of any of the rights and powers herein granted, as fully to all intents and purposes as the undersigned might or could do if personally present, with full power of substitution or revocation, hereby ratifying and confirming all that each attorney-in-fact shall lawfully do or cause to be done by virtue of this Power of Attorney and the rights and powers granted herein. The undersigned acknowledges that none of the attorneys-in-fact, in serving in such capacity at the request of the undersigned, is assuming any of the undersigned’s responsibilities to comply with Sections 13(d) or 13(g) of the Exchange Act.

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The undersigned agrees that each attorney-in-fact may rely entirely on information furnished orally or in writing by or at the direction of the undersigned to the attorney-in-fact. The undersigned also agrees to indemnify and hold harmless each attorney-in-fact against any losses, claims, damages or liabilities (or actions in these respects) that arise out of or are based upon any untrue statements or omissions of necessary facts in the information provided by or at the direction of the undersigned, or upon the lack of timeliness in the delivery of information by or at the direction of the undersigned, to the attorneys-in fact for purposes of executing, acknowledging, delivering or filing a Schedule 13D or Schedule 13G (including amendments thereto) and agrees to reimburse each attorney-in-fact on demand for any legal or other expenses reasonably incurred in connection with investigating or defending against any such loss, claim, damage, liability or action.

This Power of Attorney shall remain in full force and effect until the undersigned is no longer required to file a Schedule 13D or Schedule 13G (including amendments thereto) with respect to the undersigned’s holdings of and transactions in securities issued by Clearwire Corporation, unless earlier revoked by the undersigned in a signed writing delivered to the attorney-in-fact. This Power of Attorney does not revoke any other power of attorney that the undersigned has previously granted.

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IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be executed as of the date written below.

Exhibit 5

POWER OF ATTORNEY

FOR EXECUTING SCHEDULE 13D AND SCHEDULE 13G

The undersigned hereby constitutes and appoints each of Pamela E. Powers and David K. Schumacher, with full power of substitution, as an undersigned’s true and lawful attorney-in-fact to:

The undersigned hereby grants to each attorney-in-fact full power and authority to do and perform all and every act requisite, necessary or proper to be done in the exercise of any of the rights and powers herein granted, as fully to all intents and purposes as the undersigned might or could do if personally present, with full power of substitution or revocation, hereby ratifying and confirming all that each attorney-in-fact shall lawfully do or cause to be done by virtue of this Power of Attorney and the rights and powers granted herein. The undersigned acknowledges that none of the attorneys-in-fact, in serving in such capacity at the request of the undersigned, is assuming any of the undersigned’s responsibilities to comply with Sections 13(d) or 13(g) of the Exchange Act.

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The undersigned agrees that each attorney-in-fact may rely entirely on information furnished orally or in writing by or at the direction of the undersigned to the attorney-in-fact. The undersigned also agrees to indemnify and hold harmless each attorney-in-fact against any losses, claims, damages or liabilities (or actions in these respects) that arise out of or are based upon any untrue statements or omissions of necessary facts in the information provided by or at the direction of the undersigned, or upon the lack of timeliness in the delivery of information by or at the direction of the undersigned, to the attorneys-in fact for purposes of executing, acknowledging, delivering or filing a Schedule 13D or Schedule 13G (including amendments thereto) and agrees to reimburse each attorney-in-fact on demand for any legal or other expenses reasonably incurred in connection with investigating or defending against any such loss, claim, damage, liability or action.

This Power of Attorney shall remain in full force and effect until the undersigned is no longer required to file a Schedule 13D or Schedule 13G (including amendments thereto) with respect to the undersigned’s holdings of and transactions in securities issued by Clearwire Corporation, unless earlier revoked by the undersigned in a signed writing delivered to the attorney-in-fact. This Power of Attorney does not revoke any other power of attorney that the undersigned has previously granted.

(Signature Page Follows)

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IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be executed as of the date written below.

Exhibit 6

POWER OF ATTORNEY

FOR EXECUTING SCHEDULE 13D AND SCHEDULE 13G

The undersigned hereby constitutes and appoints each of Pamela E. Powers and David K. Schumacher, with full power of substitution, as an undersigned’s true and lawful attorney-in-fact to:

The undersigned hereby grants to each attorney-in-fact full power and authority to do and perform all and every act requisite, necessary or proper to be done in the exercise of any of the rights and powers herein granted, as fully to all intents and purposes as the undersigned might or could do if personally present, with full power of substitution or revocation, hereby ratifying and confirming all that each attorney-in-fact shall lawfully do or cause to be done by virtue of this Power of Attorney and the rights and powers granted herein. The undersigned acknowledges that none of the attorneys-in-fact, in serving in such capacity at the request of the undersigned, is assuming any of the undersigned’s responsibilities to comply with Sections 13(d) or 13(g) of the Exchange Act.

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The undersigned agrees that each attorney-in-fact may rely entirely on information furnished orally or in writing by or at the direction of the undersigned to the attorney-in-fact. The undersigned also agrees to indemnify and hold harmless each attorney-in-fact against any losses, claims, damages or liabilities (or actions in these respects) that arise out of or are based upon any untrue statements or omissions of necessary facts in the information provided by or at the direction of the undersigned, or upon the lack of timeliness in the delivery of information by or at the direction of the undersigned, to the attorneys-in fact for purposes of executing, acknowledging, delivering or filing a Schedule 13D or Schedule 13G (including amendments thereto) and agrees to reimburse each attorney-in-fact on demand for any legal or other expenses reasonably incurred in connection with investigating or defending against any such loss, claim, damage, liability or action.

This Power of Attorney shall remain in full force and effect until the undersigned is no longer required to file a Schedule 13D or Schedule 13G (including amendments thereto) with respect to the undersigned’s holdings of and transactions in securities issued by Clearwire Corporation, unless earlier revoked by the undersigned in a signed writing delivered to the attorney-in-fact. This Power of Attorney does not revoke any other power of attorney that the undersigned has previously granted.

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IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be executed as of the date written below.

Exhibit 7

POWER OF ATTORNEY

FOR EXECUTING SCHEDULE 13D AND SCHEDULE 13G

The undersigned hereby constitutes and appoints each of Pamela E. Powers and David K. Schumacher, with full power of substitution, as an undersigned’s true and lawful attorney-in-fact to:

The undersigned hereby grants to each attorney-in-fact full power and authority to do and perform all and every act requisite, necessary or proper to be done in the exercise of any of the rights and powers herein granted, as fully to all intents and purposes as the undersigned might or could do if personally present, with full power of substitution or revocation, hereby ratifying and confirming all that each attorney-in-fact shall lawfully do or cause to be done by virtue of this Power of Attorney and the rights and powers granted herein. The undersigned acknowledges that none of the attorneys-in-fact, in serving in such capacity at the request of the undersigned, is assuming any of the undersigned’s responsibilities to comply with Sections 13(d) or 13(g) of the Exchange Act.

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The undersigned agrees that each attorney-in-fact may rely entirely on information furnished orally or in writing by or at the direction of the undersigned to the attorney-in-fact. The undersigned also agrees to indemnify and hold harmless each attorney-in-fact against any losses, claims, damages or liabilities (or actions in these respects) that arise out of or are based upon any untrue statements or omissions of necessary facts in the information provided by or at the direction of the undersigned, or upon the lack of timeliness in the delivery of information by or at the direction of the undersigned, to the attorneys-in fact for purposes of executing, acknowledging, delivering or filing a Schedule 13D or Schedule 13G (including amendments thereto) and agrees to reimburse each attorney-in-fact on demand for any legal or other expenses reasonably incurred in connection with investigating or defending against any such loss, claim, damage, liability or action; provided, however, that the recourse under the foregoing indemnity shall be limited to the assets of the undersigned except in the case of gross negligence, actual fraud or willful misconduct.

This Power of Attorney shall remain in full force and effect until the undersigned is no longer required to file a Schedule 13D or Schedule 13G (including amendments thereto) with respect to the undersigned’s holdings of and transactions in securities issued by Clearwire Corporation, unless earlier revoked by the undersigned in a signed writing delivered to the attorney-in-fact. This Power of Attorney does not revoke any other power of attorney that the undersigned has previously granted.

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IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be executed as of the date written below.

Exhibit 8

POWER OF ATTORNEY

FOR EXECUTING SCHEDULE 13D AND SCHEDULE 13G

The undersigned hereby constitutes and appoints each of Pamela E. Powers and David K. Schumacher, with full power of substitution, as an undersigned’s true and lawful attorney-in-fact to:

The undersigned hereby grants to each attorney-in-fact full power and authority to do and perform all and every act requisite, necessary or proper to be done in the exercise of any of the rights and powers herein granted, as fully to all intents and purposes as the undersigned might or could do if personally present, with full power of substitution or revocation, hereby ratifying and confirming all that each attorney-in-fact shall lawfully do or cause to be done by virtue of this Power of Attorney and the rights and powers granted herein. The undersigned acknowledges that none of the attorneys-in-fact, in serving in such capacity at the request of the undersigned, is assuming any of the undersigned’s responsibilities to comply with Sections 13(d) or 13(g) of the Exchange Act.

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The undersigned agrees that each attorney-in-fact may rely entirely on information furnished orally or in writing by or at the direction of the undersigned to the attorney-in-fact. The undersigned also agrees to indemnify and hold harmless each attorney-in-fact against any losses, claims, damages or liabilities (or actions in these respects) that arise out of or are based upon any untrue statements or omissions of necessary facts in the information provided by or at the direction of the undersigned, or upon the lack of timeliness in the delivery of information by or at the direction of the undersigned, to the attorneys-in fact for purposes of executing, acknowledging, delivering or filing a Schedule 13D or Schedule 13G (including amendments thereto) and agrees to reimburse each attorney-in-fact on demand for any legal or other expenses reasonably incurred in connection with investigating or defending against any such loss, claim, damage, liability or action.

This Power of Attorney shall remain in full force and effect until the undersigned is no longer required to file a Schedule 13D or Schedule 13G (including amendments thereto) with respect to the undersigned’s holdings of and transactions in securities issued by Clearwire Corporation, unless earlier revoked by the undersigned in a signed writing delivered to the attorney-in-fact. This Power of Attorney does not revoke any other power of attorney that the undersigned has previously granted.

(Signature Page Follows)

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IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be executed as of the date written below.

Exhibit 9

POWER OF ATTORNEY

FOR EXECUTING SCHEDULE 13D AND SCHEDULE 13G

The undersigned hereby constitutes and appoints each of Pamela E. Powers and David K. Schumacher, with full power of substitution, as an undersigned’s true and lawful attorney-in-fact to:

The undersigned hereby grants to each attorney-in-fact full power and authority to do and perform all and every act requisite, necessary or proper to be done in the exercise of any of the rights and powers herein granted, as fully to all intents and purposes as the undersigned might or could do if personally present, with full power of substitution or revocation, hereby ratifying and confirming all that each attorney-in-fact shall lawfully do or cause to be done by virtue of this Power of Attorney and the rights and powers granted herein. The undersigned acknowledges that none of the attorneys-in-fact, in serving in such capacity at the request of the undersigned, is assuming any of the undersigned’s responsibilities to comply with Sections 13(d) or 13(g) of the Exchange Act.

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The undersigned agrees that each attorney-in-fact may rely entirely on information furnished orally or in writing by or at the direction of the undersigned to the attorney-in-fact. The undersigned also agrees to indemnify and hold harmless each attorney-in-fact against any losses, claims, damages or liabilities (or actions in these respects) that arise out of or are based upon any untrue statements or omissions of necessary facts in the information provided by or at the direction of the undersigned, or upon the lack of timeliness in the delivery of information by or at the direction of the undersigned, to the attorneys-in fact for purposes of executing, acknowledging, delivering or filing a Schedule 13D or Schedule 13G (including amendments thereto) and agrees to reimburse each attorney-in-fact on demand for any legal or other expenses reasonably incurred in connection with investigating or defending against any such loss, claim, damage, liability or action.

This Power of Attorney shall remain in full force and effect until the undersigned is no longer required to file a Schedule 13D or Schedule 13G (including amendments thereto) with respect to the undersigned’s holdings of and transactions in securities issued by Clearwire Corporation, unless earlier revoked by the undersigned in a signed writing delivered to the attorney-in-fact. This Power of Attorney does not revoke any other power of attorney that the undersigned has previously granted.

(Signature Page Follows)

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IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be executed as of the date written below.

Exhibit 10

POWER OF ATTORNEY

FOR EXECUTING SCHEDULE 13D AND SCHEDULE 13G

The undersigned hereby constitutes and appoints each of Pamela E. Powers and David K. Schumacher, with full power of substitution, as an undersigned’s true and lawful attorney-in-fact to:

The undersigned hereby grants to each attorney-in-fact full power and authority to do and perform all and every act requisite, necessary or proper to be done in the exercise of any of the rights and powers herein granted, as fully to all intents and purposes as the undersigned might or could do if personally present, with full power of substitution or revocation, hereby ratifying and confirming all that each attorney-in-fact shall lawfully do or cause to be done by virtue of this Power of Attorney and the rights and powers granted herein. The undersigned acknowledges that none of the attorneys-in-fact, in serving in such capacity at the request of the undersigned, is assuming any of the undersigned’s responsibilities to comply with Sections 13(d) or 13(g) of the Exchange Act.

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The undersigned agrees that each attorney-in-fact may rely entirely on information furnished orally or in writing by or at the direction of the undersigned to the attorney-in-fact. The undersigned also agrees to indemnify and hold harmless each attorney-in-fact against any losses, claims, damages or liabilities (or actions in these respects) that arise out of or are based upon any untrue statements or omissions of necessary facts in the information provided by or at the direction of the undersigned, or upon the lack of timeliness in the delivery of information by or at the direction of the undersigned, to the attorneys-in fact for purposes of executing, acknowledging, delivering or filing a Schedule 13D or Schedule 13G (including amendments thereto) and agrees to reimburse each attorney-in-fact on demand for any legal or other expenses reasonably incurred in connection with investigating or defending against any such loss, claim, damage, liability or action.

This Power of Attorney shall remain in full force and effect until the undersigned is no longer required to file a Schedule 13D or Schedule 13G (including amendments thereto) with respect to the undersigned’s holdings of and transactions in securities issued by Clearwire Corporation, unless earlier revoked by the undersigned in a signed writing delivered to the attorney-in-fact. This Power of Attorney does not revoke any other power of attorney that the undersigned has previously granted.

(Signature Page Follows)

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IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be executed as of the date written below.