Exhibit 4

AMENDMENT NO. 1 TO RIGHTS AGREEMENT

THIS AMENDMENT NO. 1 TO RIGHTS AGREEMENT (the “Amendment”) is dated as of July 3, 2008, between Capstone Turbine Corporation, a Delaware corporation (the “Company”), and Mellon Investor Services LLC (the “Rights Agent”).

W I T N E S S E T H

WHEREAS, the Company and the Rights Agent are parties to a Rights Agreement, dated as of July 7, 2005 (the “Agreement”); and

WHEREAS, the Company and the Rights Agent desire to amend certain terms and provisions of the Agreement as set forth in this Amendment.

NOW, THEREFORE, in consideration of the foregoing premises, the mutual covenants and other agreements set forth herein, and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto covenant and agree as follows:

1. Certain Definitions

(a) Definition of “Acquiring Person.” The definition of the term “Acquiring Person” contained in Section 1 of the Agreement is hereby amended and restated in its entirety by the following:

“Acquiring Person” shall mean any Person who or which, together with all Affiliates and Associates of such Person, shall be the Beneficial Owner of 20% or more of the shares of Common Stock then outstanding, but shall not include (i) the Company, (ii) any Subsidiary of the Company, (iii) any employee benefit plan of the Company or of any Subsidiary of the Company, or any Person or entity organized, appointed or established by the Company for or pursuant to the terms of any such plan, or (iv) any Person who becomes the Beneficial Owner of 20% or more of the shares of Common Stock then outstanding as a result of a reduction in the number of shares of Common Stock outstanding due to the repurchase of shares of Common Stock by the Company unless and until such Person, after becoming aware that such Person has become the Beneficial Owner of 20% or more of the then outstanding shares of Common Stock, acquires beneficial ownership of additional shares of Common Stock representing 1% or more of the shares of Common Stock then outstanding.

(b) Definition of “Definitive Acquisition Agreement”. The definition of the term “Definitive Acquisition Agreement” is hereby added to Section 1 of the Agreement and shall read as follows:

“Definitive Acquisition Agreement” shall mean an agreement, conditioned on the approval by the holders of not less than a majority of the outstanding shares of Common Stock, with respect to a merger, recapitalization, share exchange, or a similar transaction involving the Company or the direct or indirect acquisition of more than 50 percent of the Company’s consolidated total assets.

(c) Definition of “Exemption Date”. The definition of the term “Exemption Date” is hereby added to Section 1 of the Agreement and shall read as follows:

“Exemption Date” shall have the meaning set forth in Section 23(b) hereof.

(d) Definition of “Outside Meeting Date”. The definition of the term “Outside Meeting Date” is hereby added to Section 1 of the Agreement and shall read as follows:

“Outside Meeting Date” shall have the meaning set forth in Section 23(b) hereof.

(e) Definition of “Qualified Offer”. The term “Qualified Offer” is hereby deleted in its entirety.

(f) Definition of “Qualifying Offer”. The definition of the term “Qualifying Offer” is hereby added to Section 1 of the Agreement and shall read as follows:

“Qualifying Offer” shall mean an offer determined by a majority of independent directors of the Company to have, to the extent required for the type of offer specified, each of the following characteristics:

(i) a fully financed all-cash tender offer or an exchange offer offering shares of common stock of the offeror, or a combination thereof, in each such case for any and all of the outstanding shares of Common Stock at the same per share consideration; provided, however, that such per share price and consideration represent a reasonable premium over the highest reported market price of the Common Stock in the immediately preceding 24 months, with, in the case of an offer that includes shares of common stock of the offeror, such per share offer price being determined using the lowest reported market price for common stock of the offeror during the five Trading Days immediately preceding and the five Trading Days immediately following the date on which the Qualifying Offer is commenced;

(ii) an offer that has commenced within the meaning of Rule 14d-2(a) under the Exchange Act and is made by an offeror (including Affiliates and/or Associates of such offeror) that beneficially owns no more than 1 percent of the outstanding Common Stock as of the date of such commencement;

(iii) an offer that, within 20 Business Days after the commencement date of the offer (or within 10 Business Days after any increase in the offer consideration), does not result in a nationally recognized investment banking firm retained by the Board rendering an opinion to the Board that the consideration being offered to the stockholders of the Company is either unfair or inadequate;

(iv) if the offer includes shares of common stock of the offeror, an offer pursuant to which (i) the offeror shall permit representatives of the Company, including, without limitation, a nationally recognized investment banking firm retained by the Board, legal counsel and an accounting firm designated by the Company to have access to such offeror’s books, records, management, accountants and other appropriate outside advisers for the purposes of permitting such representatives to conduct a due diligence review of the offeror in order to permit such investment banking firm (relying as appropriate on the advice of such legal counsel) to be able to render an opinion to the Board with respect to whether the consideration being offered to the Company’s stockholders is fair, and (ii) within 10 Business Days after such investment banking firm shall have notified the Company and the offeror that it had completed the due diligence review to its satisfaction (or following completion of such due diligence review within 10 Business Days after any increase in the consideration being offered), such investment banking firm does not render an opinion to the Board that the consideration being offered to the stockholders of the Company is either unfair or inadequate and such investment banking firm does not after the expiration of such 10 Business Day period render an opinion to the Board that the consideration being offered to the stockholders of the Company has become either unfair or inadequate based on a subsequent disclosure or discovery of a development or developments that have had or are reasonably likely to have a material adverse affect on the value of the common stock of the offeror;

(v) an offer that is subject only to the minimum tender condition described below in item (viii) of this definition and other customary terms and conditions, which conditions shall not include any financing, funding or similar conditions or any requirements with respect to the offeror or its agents being permitted any due diligence with respect to the books, records, management, accountants or any other outside advisers of the Company;

(vi) an offer pursuant to which the Company and its stockholders have received an irrevocable written commitment of the offeror that the offer will remain open for not less than 120 Business Days and, if a Special Meeting Demand is duly delivered to the Board in accordance with Section 23(b), for at least 10 Business Days after the date of the Special Meeting or, if no Special Meeting is held within the Special Meeting Period (as defined in Section 23(b)), for at least 10 Business Days following the last day of such Special Meeting Period (the “Qualifying Offer Period”);

(vii) an offer pursuant to which the Company has received an irrevocable written commitment by the offeror that, in addition to the minimum time periods specified in item (vi) of this definition, the offer, if it is otherwise to expire prior thereto, will be extended for at least 15 Business Days after (i) any increase in the price offered, or (ii) any bona fide alternative offer is commenced by another Person within the meaning of Rule 14d-2(a) of the Exchange Act; provided, however, that such offer need not remain open, as a result of clauses (vi) and (vii) of this definition, beyond (1) the time which any other offer satisfying the criteria for a Qualifying Offer is then required to be kept open under such clauses (vi) and (vii), or (2) the expiration date, as such date may be extended by public announcement (with prompt written notice to the Rights Agent) in compliance with Rule 14e-1 of the Exchange Act, of any other tender offer for the Common Stock with respect to which the Board has agreed to redeem the Rights immediately prior to acceptance for payment of Common

Stock thereunder (unless such other offer is terminated prior to its expiration without any Common Stock having been purchased thereunder) or (3) one Business Day after the stockholder vote with respect to approval of any Definitive Acquisition Agreement has been officially determined and certified by the inspectors of elections;

(viii) an offer that is conditioned on a minimum of at least a majority of the outstanding shares of the Common Stock being tendered and not withdrawn as of the offer’s expiration date, which condition shall not be waivable;

(ix) an offer pursuant to which the Company and its stockholders have received an irrevocable written commitment by the offeror to consummate as promptly as practicable upon successful completion of the offer a second step transaction whereby all shares of the Common Stock not tendered into the offer will be acquired at the same consideration per share actually paid pursuant to the offer, subject to stockholders’ statutory appraisal rights, if any;

(x) an offer pursuant to which the Company and its stockholders have received an irrevocable written commitment of the offeror that no amendments will be made to the offer to reduce the offer consideration, or otherwise change the terms of the offer in a way that is materially adverse to a tendering stockholder (other than extensions of the offer consistent with the terms thereof);

(xi) an offer (other than an offer consisting solely of cash consideration) pursuant to which the Company has received the written representation and certification of the offeror and, in their individual capacities, the written representations and certifications of the offeror’s Chief Executive Officer and Chief Financial Officer, that (i) all facts about the offeror that would be material to making an investor’s decision to accept the offer have been fully and accurately disclosed as of the date of the commencement of the offer within the meaning of Rule 14d-2(a) of the Exchange Act, (ii) all such new facts will be fully and accurately disclosed on a prompt basis during the entire period during which the offer remains open, and (iii) all required Exchange Act reports will be filed by the offeror in a timely manner during such period; and

(xii) if the offer includes shares of stock of the offeror, (i) the stock portion of the consideration must consist solely of common stock of an offeror that is a publicly owned corporation, and be freely tradable and is listed on either the New York Stock Exchange or the NASDAQ National Market System, (ii) no stockholder approval of the offeror is required to issue such common stock, or, if required, has already been obtained, (iii) no Person (including such Person’s Affiliates and Associates) beneficially owns more than 20 percent of the voting stock of the offeror at the time of commencement of the offer or at any time during the term of the offer, and (iv) no other class of voting stock of the offeror is outstanding, and the offeror meets the registrant eligibility requirements for use of Form S-3 for registering securities under the Act; including, without limitation, the filing of all required Exchange Act reports in a timely manner during the 12 calendar months prior to the date of commencement of the offer.

For the purposes of the definition of Qualifying Offer, “fully financed” shall mean that the offeror has sufficient funds for the offer and related expenses which shall be evidenced by (i) firm, unqualified, written commitments from responsible financial institutions having the necessary financial capacity, accepted by the offeror, to provide funds for such offer subject only to customary terms and conditions, (ii) cash or cash equivalents then available to the offeror, set apart and maintained solely for the purpose of funding the offer with an irrevocable written commitment being provided by the offeror to the Board to maintain such availability until the offer is consummated or withdrawn, or (iii) a combination of the foregoing; which evidence has been provided to the Company prior to, or upon, commencement of the offer. If an offer becomes a Qualifying Offer in accordance with this definition but subsequently ceases to be a Qualifying Offer as a result of the failure at a later date to continue to satisfy any of the requirements of this definition, such offer shall cease to be a Qualifying Offer and the provisions of Section 23(b) shall no longer be applicable to such offer.

(g) Definition of “Qualifying Offer Period”. The definition of the term “Qualifying Offer Period” is hereby added to Section 1 of the Agreement and shall read as follows:

“Qualifying Offer Period” shall have the meaning set forth in the definition of Qualifying Offer.

(h) Definition of “Qualifying Offer Resolution”. The definition of the term “Qualifying Offer Resolution” is hereby added to Section 1 of the Agreement and shall read as follows:

“Qualifying Offer Resolution” shall have the meaning set forth in Section 23(b) hereof.

(i) Definition of “Special Meeting”. The definition of the term “Special Meeting” is hereby added to Section 1 of the Agreement and shall read as follows:

“Special Meeting” shall have the meaning set forth in Section 23(b) hereof.

(j) Definition of “Special Meeting Demand”. The definition of the term “Special Meeting Demand” is hereby added to Section 1 of the Agreement and shall read as follows:

“Special Meeting Demand” shall have the meaning set forth in Section 23(b) hereof.

(k) Definition of “Special Meeting Period”. The definition of the term “Special Meeting Period” is hereby added to Section 1 of the Agreement and shall read as follows:

“Special Meeting Period” shall have the meaning set forth in Section 23(b) hereof.

(l) Definition of “Stock Acquisition Date”. The definition of the term “Stock Acquisition Date” contained in Section 1 of the Agreement is hereby amended and restated in its entirety by the following:

“Stock Acquisition Date” shall mean the first date of public announcement (which, for purposes of this definition, shall include, without limitation, a report filed or amended pursuant to Section 13(d) under the Exchange Act) by the Company or an Acquiring Person that an Acquiring Person has become such.

2. Amendment of Section 3(a). Section 3(a) of the Agreement is hereby amended and restated in its entirety as set forth below:

(a) Until the earlier of (i) the close of business on the tenth day after the Stock Acquisition Date (or, if the tenth day after the Stock Acquisition Date occurs before the Record Date, the close of business on the Record Date), or (ii) the close of business on the tenth day (or such later date as the Board shall determine) after the date that a tender or exchange offer by any Person (other than the Company, any Subsidiary of the Company, any employee benefit plan of the Company or of any Subsidiary of the Company, or any Person or entity organized, appointed or established by the Company for or pursuant to the terms of any such plan) is first published or sent or given within the meaning of Rule 14d-2(a) of the General Rules and Regulations under the Exchange Act, if upon consummation thereof, such Person would become an Acquiring Person (the earlier of (i) and (ii) being herein referred to as the “Distribution Date”),(x) the Rights will be represented (subject to the provisions of paragraph (b) of this Section 3) by the certificates for the Common Stock registered in the names of the holders of the Common Stock (which certificates for Common Stock shall be deemed also to be certificates for Rights) and not by separate certificates, and (y) the Rights will be transferable only in connection with the transfer of the underlying shares of Common Stock (including a transfer to the Company). As soon as practicable after the Company has notified the Rights Agent of the occurrence of the Distribution Date, the Company will prepare and execute, and the Company will deliver to the Rights Agent to be countersigned, which the Rights Agent shall do, and the Company (or the Rights Agent, if so requested by the Company in writing, and provided with a stockholder list and all other relevant information which the Rights Agent may reasonably request) shall send or cause to be sent, by first-class, insured, postage-prepaid mail, to each record holder of the Common Stock as of the close of business on the Distribution Date, at the address of such holder shown on the records of the Company, one or more right certificates, in substantially the form of Exhibit B hereto (the “Rights Certificates”), representing one Right for each share of Common Stock so held, subject to adjustment as provided herein. In the event that an adjustment in the number of Rights per share of Common Stock has been made pursuant to Section 11(p) hereof, at the time of distribution of the Rights Certificates, the Company shall make the necessary and appropriate rounding adjustments (in accordance with Section 14(a) hereof) so that Rights Certificates representing only whole numbers of Rights are distributed and cash is paid in lieu of any fractional Rights. As of and after the Distribution Date, the Rights will be represented solely by such Rights Certificates. The Company shall notify the Rights Agent in writing upon the occurrence of the Distribution Date. Until such notice is received by the Rights Agent, the Rights Agent may presume conclusively for all purposes that the Distribution Date has not occurred.

3. Amendment of Section 11(a)(ii). Section 11(a)(ii) of the Agreement is hereby amended and restated in its entirety as set forth below:

(ii) In the event any Person shall, at any time after the Rights Dividend Declaration Date, become an Acquiring Person, unless the event causing such Person to become an Acquiring Person is a transaction set forth in Section 13(a) hereof, then, promptly following the occurrence of such event, proper provision shall be made so that each holder of a Right (except as provided below and in Section 7(e) hereof) shall thereafter have the right to receive, upon exercise thereof at the then current Purchase Price in accordance with the terms of this Agreement, in lieu of a number of one one-hundredths of a share of Preferred Stock, such number of shares of Common Stock of the Company as shall equal the result obtained by (x) multiplying the then current Purchase Price by the then number of one one-hundredths of a share of Preferred Stock for which a Right was exercisable immediately prior to the first occurrence of a Section 11(a)(ii) Event, and (y) dividing that product (which, following such first occurrence, shall thereafter be referred to as the “Purchase Price” for each Right and for all purposes of this Agreement) by 50% of the Current Market Price (determined pursuant to Section 11(d) hereof) per share of Common Stock on the date of such first occurrence (such number of shares, the “Adjustment Shares”).

4. Section 13(a). Section 13(a) of the Agreement is hereby amended and restated in its entirety as set forth below:

(a) In the event that, following the Stock Acquisition Date, directly or indirectly, (x) the Company shall consolidate with, or merge with and into, any other Person (other than a Subsidiary of the Company in a transaction which complies with Section 11(o) hereof), and the Company shall not be the continuing or surviving corporation of such consolidation or merger, (y) any Person (other than a Subsidiary of the Company in a transaction which complies with Section 11(o) hereof) shall consolidate with, or merge with or into, the Company, and the Company shall be the continuing or surviving corporation of such consolidation or merger and, in connection with such consolidation or merger, all or part of the outstanding shares of Common Stock shall be changed into or exchanged for stock or other securities of any other Person or cash or any other property, or (z) the Company shall sell or otherwise transfer (or one or more of its Subsidiaries shall sell or otherwise transfer), in one transaction or a series of related transactions, assets, cash flow or earning power aggregating more than 50% of the assets, cash flow or earning power of the Company and its Subsidiaries (taken as a whole) to any Person or Persons (other than the Company or any Subsidiary of the Company in one or more transactions each of which complies with Section 11(o) hereof), then, and in each such case, proper provision shall be made so that: (i) each holder of a Right, except as provided in Section 7(e) hereof, shall thereafter have the right to receive, upon the exercise thereof at the then current Purchase Price in accordance with the terms of this Agreement, such number of validly authorized and issued, fully paid, non-assessable and freely tradeable shares of Common Stock of the Principal Party (as hereinafter defined), not subject to any liens, encumbrances, rights of first refusal or other adverse claims, as shall be equal to the result obtained by (1) multiplying the then current Purchase Price by the number of one one-hundredths of a share of Preferred Stock for which a Right is exercisable immediately prior to the first occurrence of a Section 13 Event (or, if a Section 11(a)(ii) Event has occurred prior to the first occurrence of a Section 13 Event, multiplying the number of such one one-hundredths of a share for which a Right was exercisable immediately prior to the first occurrence of a Section 11(a)(ii) Event by the Purchase Price in effect immediately prior to such first occurrence), and dividing that product (which, following the first occurrence of a Section 13 Event, shall be referred to as the “Purchase Price” for each Right and for all purposes of this Agreement) by (2) 50% of the Current Market Price (determined pursuant to Section 11(d)(i) hereof) per share of the Common Stock of such Principal Party on the date of consummation of such Section 13 Event; (ii) such Principal Party shall thereafter be liable for, and shall assume, by

virtue of such Section 13 Event, all the obligations and duties of the Company pursuant to this Agreement; (iii) the term “Company” shall thereafter be deemed to refer to such Principal Party, it being specifically intended that the provisions of Section 11 hereof shall apply only to such Principal Party following the first occurrence of a Section 13 Event; (iv) such Principal Party shall take such steps (including, but not limited to, the reservation of a sufficient number of shares of its Common Stock) in connection with the consummation of any such transaction as may be necessary to assure that the provisions hereof shall thereafter be applicable, as nearly as reasonably may be, in relation to its shares of Common Stock thereafter deliverable upon the exercise of the Rights; and (v) the provisions of Section 11(a)(ii) hereof shall be of no effect following the first occurrence of any Section 13 Event.

5. Section 13(d). Section 13(d) of the Agreement is hereby deleted in its entirety.

6. Amendment of Section 20(b). Section 20(b) of the Agreement is hereby amended and restated in its entirety as set forth below:

(b) Whenever in the performance of its duties under this Agreement the Rights Agent shall deem it necessary or desirable that any fact or matter (including, without limitation, the identity of any Acquiring Person, the determination of Current Market Price and the existence of a Qualifying Offer) be proved or established by the Company prior to taking or suffering or omitting to take any action hereunder, such fact or matter (unless other evidence in respect thereof be herein specifically prescribed) may be deemed to be conclusively proved and established by a certificate signed by the Chairman of the Board, the Chief Executive Officer, the President, any Vice President, the Treasurer, any Assistant Treasurer, the Secretary or any Assistant Secretary of the Company and delivered to the Rights Agent; and such certificate shall be full and complete authorization and protection to the Rights Agent and the Rights Agent shall incur no liability for or in respect of any action taken, suffered or omitted by it in the absence of bad faith under the provisions of this Agreement in reliance upon such certificate.

7. Amendment of Section 23. Section 23 of the Agreement is hereby amended and restated in its entirety as set forth below:

Section 23. Redemption and Termination.

(a) The Company may, at its option, at any time prior to the earlier of (i) the close of business on the tenth day following the Stock Acquisition Date (or, if the Stock Acquisition Date shall have occurred prior to the Record Date, the close of business on the tenth day following the Record Date), or (ii) the Final Expiration Date, redeem all but not less than all of the then outstanding Rights at a redemption price of $.0001 per Right, as such amount may be appropriately adjusted to reflect any stock split, stock dividend or similar transaction occurring after the date hereof (such redemption price being hereinafter referred to as the “Redemption Price”). Notwithstanding anything contained in this Agreement to the contrary, the Rights shall not be exercisable after the first occurrence of a Section 11(a)(ii) Event until such time as the Company’s right of redemption hereunder has expired. The Company may, at its option, pay the Redemption Price in cash, shares of Common Stock (based on the Current Market Price, as defined in Section 11(d)(i) hereof, of the Common Stock at the time of redemption) or any other form of consideration deemed appropriate by the Board.

(b) In the event the Company receives a Qualifying Offer and the Board has not redeemed the outstanding Rights or exempted such offer from the terms of this Agreement or called a special meeting of stockholders by the end of the 90^th Business Day following the commencement (or, if later, the first existence) of a Qualifying Offer, for the purpose of voting on whether or not to exempt such

Qualifying Offer from the terms of this Agreement, holders of record (or their duly authorized proxy) of at least 10% of the shares of Common Stock then outstanding may submit to the Board, not earlier than 90 Business Days nor later than 120 Business Days following the commencement (or, if later, the first existence) of such Qualifying Offer, a written demand complying with the terms of this Section 23(b) (the “Special Meeting Demand”) directing the Board to submit to a vote of stockholders at a special meeting of the stockholders of the Company (a “Special Meeting”) a resolution exempting such Qualifying Offer from the provisions of this Agreement (the “Qualifying Offer Resolution”). For purposes of a Special Meeting Demand, the record date for determining holders of record eligible to make a Special Meeting Demand shall be the 90th Business Day following commencement (or, if later, the first existence) of a Qualifying Offer. The Board shall take such actions as are necessary or desirable to cause the Qualifying Offer Resolution to be so submitted to a vote of stockholders at a Special Meeting to be convened within 90 Business Days following the Special Meeting Demand (the “Special Meeting Period”); provided, however, that if the Company at any time during the Special Meeting Period and prior to a vote on the Qualifying Offer Resolution enters into a Definitive Acquisition Agreement, the Special Meeting Period may be extended (and any special meeting called in connection therewith may be cancelled) if the Qualifying Offer Resolution will be separately submitted to a vote at the same meeting as the Definitive Acquisition Agreement. A Special Meeting Demand must be delivered to the Secretary of the Company at the principal executive offices of the Company and must set forth as to the stockholders of record making the request (x) the names and addresses of such stockholders, as they appear on the Company’s books and records, (y) the class and number of shares of Common Stock which are owned of record by each of such stockholders, and (z) in the case of Common Stock that is owned beneficially by another Person, an executed certification by the holder of record that such holder has executed such Special Meeting Demand only after obtaining instructions to do so from such beneficial owner and attaching evidence thereof. Subject to the requirements of applicable law, the Board may take a position in favor of or opposed to the adoption of the Qualifying Offer Resolution, or no position with respect to the Qualifying Offer Resolution, as it determines to be appropriate in the exercise of its duties. In the event that no Person has become an Acquiring Person prior to the redemption date referred to in this Section 23(b), and the Qualifying Offer continues to be a Qualifying Offer and either (i) the Special Meeting is not convened on or prior to the last day of the Special Meeting Period (the “Outside Meeting Date”), or (ii) if, at the Special Meeting at which a quorum is present, a majority of the shares of Common Stock present or represented by proxy at the Special Meeting and entitled to vote thereon as of the record date for the Special Meeting selected by the Board shall vote in favor of the Qualifying Offer Resolution, then the Qualifying Offer shall be deemed exempt from the application of this Agreement to such Qualifying Offer so long as it remains a Qualifying Offer, such exemption to be effective on the Close of Business on the tenth Business Day after (i) the Outside Meeting Date or (ii) the date on which the results of the vote on the Qualifying Offer Resolution at the Special Meeting are certified as official by the appointed inspectors of election for the Special Meeting, as the case may be (the “Exemption Date”). Notwithstanding anything herein to the contrary, no action or vote, including action by written consent, by stockholders not in compliance with the provisions of this Section 23(b) shall serve to exempt any offer from the terms of this Agreement.

(c) Immediately upon the action of the Board authorizing the redemption of the Rights, evidence of which shall have been filed with the Rights Agent and without any further action and without any notice, the right to exercise the Rights will terminate and the only right thereafter of the holders of Rights shall be to receive the Redemption Price for each Right so held. Promptly after the action of the Board authorizing the redemption of the Rights, the Company shall give notice of such redemption to the Rights Agent and the holders of the then outstanding Rights by mailing such notice to all such holders at each holder’s last address as it appears upon the registry books of the Rights Agent or, prior to the Distribution Date, on the registry books of the transfer agent for the Common Stock. Any notice which is mailed in the manner herein provided shall be deemed given, whether or not the holder receives the notice. Each such notice of redemption will state the method by which the payment of the Redemption Price will be made.

(d) Immediately upon the Close of Business on the Exemption Date, without any further action and without any notice, the right to exercise the Rights with respect to the Qualifying Offer will terminate.

(e) Notwithstanding anything contained in this Agreement to the contrary, all the Rights outstanding at the close of business on the 30th day after the Company’s 2008 annual meeting of stockholders shall automatically be redeemed at the Redemption Price, without any further action being taken by the Board, unless continuation of this Agreement is approved by the stockholders of the Company at that meeting. If continuation of the Agreement is approved at such meeting, all the Rights outstanding at the close of business on the 30th day after the Company’s 2011 annual meeting of stockholders shall automatically be redeemed at the Redemption Price, without any further action being taken by the Board, unless continuation of this Agreement is approved by the stockholders of the Company at that meeting. As promptly as practicable following any such redemption, the Company shall make arrangements to mail a notice of redemption to, and to make appropriate payments with respect to Rights held by, holders of record of Rights as of the close of business on such redemption date. On such redemption date, and without further action and without any notice, the right thereafter of the holders of Rights shall be to receive the Redemption Price for each Right so held. The notice of redemption shall be mailed to the holder’s last address as it appears on the registry books of the Rights Agent or, prior to the Distribution Date, on the registry books of the Transfer Agent of the Common Stock. Any notice which is mailed in the manner herein provided shall be deemed given, whether or not the holder receives the notice. The notice of redemption shall state the method by which the payment of the Redemption Price shall be made, unless the notice is mailed together with such payment.

8. Exhibit C. Exhibit C to the Agreement is hereby amended and restated in its entirety as set forth in the form of Exhibit C attached hereto.

9. Amendment. This Amendment is made pursuant to and compliant in all respects with Section 27 of the Agreement. Except as expressly amended hereby, the Agreement shall remain in full force and effect.

10. Counterparts. This Amendment may be executed in two or more counterparts, each and all of which shall be deemed an original and all of which together shall constitute but one and the same instrument. A facsimile signature shall be considered the same as an original signature for purposes of execution of this Amendment.

[The following page is the signature page.]

IN WITNESS WHEREOF, the parties have caused this Amendment No. 1 to Rights Agreement to be executed as of the date first above written.

COMPANY:

CAPSTONE TURBINE CORPORATION


By:	/s/ Edward Reich

Title:		Executive Vice President and Chief Financial Officer



RIGHTS AGENT:

MELLON INVESTOR SERVICES LLC


By:	/s/ James Kirkland

Title:		Assistant Vice President

EXHIBIT C

SUMMARY OF RIGHTS TO PURCHASE
PREFERRED STOCK

On July 5, 2005, the Board of Directors (the “Board”) of Capstone Turbine Corporation, (the “Company”) authorized a dividend distribution of one Right for each authorized and outstanding share of common stock, par value $0.001 per share (the “Common Stock”), of the Company to stockholders of record at the close of business on July 18, 2005 (the “Record Date”). Each Right entitles the registered holder to purchase from the Company a unit consisting of one one-hundredth of a share (a “Unit”) of Series A Junior Participating Preferred Stock, par value $0.001 per share (the “Series A Preferred Stock”) at a Purchase Price of $10.00 per Unit, subject to adjustment. The description and terms of the Rights are set forth in a Rights Agreement, as amended (the “Rights Agreement”) between the Company and Mellon Investor Services LLC, as Rights Agent. Terms used but not defined in this summary have the meanings ascribed to them in the Rights Agreement.

Initially, the Rights will be attached to all Common Stock certificates representing shares then outstanding, and no separate Rights Certificates will be distributed. Subject to certain exceptions specified in the Rights Agreement, the Rights will separate from the Common Stock and a Distribution Date will occur upon the earlier of (i) 10 days following a public announcement that a person or group of affiliated or associated persons (an “Acquiring Person”) has subject to certain exceptions acquired, or obtained the right to acquire, beneficial ownership of 20% or more of the outstanding shares of Common Stock (the “Stock Acquisition Date”), other than as a result of repurchases of stock by the Company or certain inadvertent actions by institutional or certain other stockholders, or (ii) 10 days (or such later date as the Board shall determine) following the commencement of a tender offer or exchange offer that would result in a person or group beneficially owning 20% or more of the outstanding shares of Common Stock.

Until the Distribution Date, (i) the Rights will be represented by Common Stock certificates and will be transferred with and only with such Common Stock certificates, (ii) new Common Stock certificates issued after the Record Date will contain a notation incorporating the Rights Agreement by reference and (iii) the surrender for transfer of any certificates for Common Stock outstanding will also constitute the transfer of the Rights associated with the Common Stock represented by such certificate. Pursuant to the Rights Agreement, the Company reserves the right to require prior to the occurrence of a Triggering Event (as defined below) that, upon any exercise of Rights, a number of Rights be exercised so that only whole shares of Preferred Stock will be issued.

The Rights are not exercisable until the Distribution Date and will expire at 5:00 P.M. (California time) on July 18, 2015, unless such date is extended or the Rights are earlier redeemed or exchanged by the Company as described below (including by virtue of the “sunset provision”).

As soon as practicable after the Distribution Date, Rights Certificates will be mailed to holders of record of the Common Stock as of the close of business on the Distribution Date and, thereafter, the separate Rights Certificates alone will represent the Rights. Except as otherwise determined by the Board, only shares of Common Stock issued prior to the Distribution Date will be issued with Rights.

In the event that a Person becomes an Acquiring Person, each holder of a Right will thereafter have the right to receive, upon exercise, in lieu of the fractional shares of Series A Preferred Stock, that number of shares of Common Stock (or, in certain circumstances, cash, property or other securities of the Company) having a value equal to two times the exercise price of the Right. Notwithstanding any of the foregoing, following the occurrence of the event set forth in this paragraph, all Rights that are, or (under

certain circumstances specified in the Rights Agreement) were, beneficially owned by any Acquiring Person will be null and void. However, Rights are not exercisable following the occurrence of the event set forth above until such time as the Rights are no longer redeemable by the Company as set forth below.

For example, at an exercise price of $10.00 per Right, each Right not owned by an Acquiring Person (or by certain related parties) following an event set forth in the preceding paragraph would entitle its holder to purchase $20.00 worth of Common Stock (or other consideration, as noted above) for $10.00. Assuming that the Common Stock had a per share value of $1.00 at such time, the holder of each valid Right would be entitled to purchase twenty shares of Common Stock for $10.00.

In the event that, at any time following the Stock Acquisition Date, (i) the Company engages in a merger or other business combination transaction in which the Company is not the surviving corporation, (ii) the Company engages in a merger or other business combination transaction in which the Company is the surviving corporation and the Common Stock of the Company is changed or exchanged, or (iii) 50% or more of the Company’s assets, cash flow or earning power is sold or transferred, each holder of a Right (except Rights which have previously been voided as set forth above) shall thereafter have the right to receive, upon exercise, common stock of the acquiring company having a value equal to two times the exercise price of the Right. The events set forth in this paragraph and in the second preceding paragraph are referred to as the “Triggering Events.”

At any time after a person becomes an Acquiring Person and prior to the acquisition by such person or group of fifty percent (50%) or more of the outstanding Common Stock, the Company may exchange the Rights (other than Rights owned by such person or group which have become void), in whole or in part, at an exchange ratio of one share of Common Stock, or one one-hundredth of a share of Series A Preferred Stock (or of a share of a class or series of the Company’s preferred stock having equivalent rights, preferences and privileges), per Right (subject to adjustment).

At any time until ten days following the Stock Acquisition Date, the Company may redeem the Rights in whole, but not in part, at a price of $0.0001 per Right (payable in cash, Common Stock or other consideration deemed appropriate by the Board). Immediately upon the action of the Board authorizing redemption of the Rights, the Rights will terminate and the only right of the holders of Rights will be to receive the $0.0001 redemption price.

The Rights Agreement further provides that in the event the Company receives a Qualifying Offer (that has not been terminated prior thereto and which continues to be a Qualifying Offer), stockholders representing at least 10% of the shares of Common Stock then outstanding may request that the Board call a special meeting of stockholders to vote to exempt the Qualifying Offer from the operation of the Rights Agreement not earlier than 90, nor later than 120, business days following the commencement of such offer. The Board must then call and hold such a meeting to vote on exempting such offer from the terms of the Rights Agreement within the 90th business day following receipt of the stockholder demand for the meeting; provided that such period may be extended if, prior to the vote, the Company enters into an agreement (that is conditioned on the approval by the holders of not less than a majority of the outstanding shares of Common Stock) with respect to a merger, recapitalization, share exchange, or a similar transaction involving the Company or the direct or indirect acquisition of more than 50% of the Company’s consolidated total assets (a “Definitive Acquisition Agreement”), until the time of the meeting at which the stockholders will be asked to vote on the Definitive Acquisition Agreement. If no Acquiring Person has emerged, the offer continues to be a Qualifying Offer and stockholders representing at least a majority of the shares of Common Stock represented at the meeting at which a quorum is present vote in favor of redeeming the rights, then such Qualifying Offer shall be deemed exempt from the Rights Agreement on the date that the vote results are certified. If no Acquiring Person has emerged and no special meeting is held by the date required, the Rights will be redeemed at the close of business on the tenth business day following that date.

A Qualifying Offer, in summary terms, is an offer determined by the Board to have each of the following characteristics which are generally intended to preclude offers that are coercive, abusive, or clearly illegitimate:

· is an all-cash tender offer or stock exchange offer or combination thereof for any and all of the outstanding shares of Common Stock of the Company;

· is an offer that has commenced within the meaning of Rule 14d-2(a) under the Securities Exchange Act of 1934, as amended, and is made by an offeror (including its affiliates or associates) that beneficially owns no more than 1% of the outstanding Common Stock of the Company as of the date of such commencement;

· is an offer whose per-share price represents a reasonable premium over the highest market price of the Common Stock in the preceding 24 months, with, in the case of an offer that includes shares of common stock of the offeror, such per-share offer price being determined using the lowest reported market price for common stock of the offeror during the five trading days immediately preceding and the five trading days immediately following the commencement of the offer;

· is an offer which, within 20 business days after the commencement date of the offer (or within 10 business days after any increase in the offer consideration), does not result in a nationally recognized investment banking firm retained by the Board rendering an opinion to the Board that the consideration being offered to the Company’s stockholders is either unfair or inadequate;

· is subject only to the minimum tender condition described below and other customary terms and conditions, which conditions shall not include any requirements with respect to the offeror or its agents being permitted to conduct any due diligence with respect to the books, records, management, accountants and other outside advisers of the Company;

· is accompanied by an irrevocable written commitment by the offeror to the Company that the offer will remain open for at least 120 business days and, if a special meeting is duly requested by Capstone’s stockholders with respect to the offer, at least 10 business days after the date of the special meeting or, if no special meeting is held within 90 business days following receipt of the notice of the special meeting, for at least 10 business days following that 90-day period;

· is accompanied by an irrevocable written commitment by the offeror to the Company that, in addition to the minimum time periods specified above, the offer will be extended for at least 15 business days after any increase in the price offered, and after any bona fide alternative offer is made;

· is conditioned on a minimum of a majority of the shares of Common Stock of the Company being tendered and not withdrawn as of the offer’s expiration date;

· is accompanied by an irrevocable written commitment by the offeror to the Company to consummate promptly upon successful completion of the offer a second-step transaction whereby all shares of Common Stock of the Company not tendered into the offer will be acquired at the same consideration per share actually paid pursuant to the offer, subject to stockholders’ statutory appraisal rights, if any;

· is accompanied by an irrevocable written commitment by the offeror to the Company that no amendments will be made to the offer to reduce the offer consideration or otherwise change the terms of the offer in a way that is adverse to a tendering stockholder; and

· is accompanied by certifications of the offeror and its chief executive officer and chief financial officer (in their individual capacities) that all information that may be material to an investor’s decision to accept the offer have been, and will continue to be promptly for the pendency of the offer, fully and accurately disclosed.

Any offers that have cash as all or partial consideration are subject to further conditions for qualification as “qualifying offers,” as set forth in the Rights Agreement. These conditions generally require assurance that the offer is fully financed and that the offeror has sufficient committed resources to consummate the offer. Any offers that have acquiror common stock as all or partial consideration are subject to further conditions for qualification as “qualifying offers,” as set forth in the Rights Agreement. These conditions generally require certain safeguards regarding, and access to, information about the acquiror to allow an informed determination as to the value and risks of the stock, including safeguards against developments that adversely affect the value of the stock, that the acquiror’s stock (which may not have subordinated voting rights nor may its ownership be heavily concentrated in one person or group) is listed on a national exchange, that the acquiror meets certain seasoned issuer standards under the Securities Act of 1933, and that no acquiror stockholder approval of the issuance of the consideration to the Company stockholders is necessary after commencement of the offer.

Pursuant to the “sunset provision” contained in the Rights Agreement, continuation of the Rights Agreement will be put to a vote of the Company’s stockholders at the Company’s 2011 annual meeting of stockholders. If the majority of the shares of Common Stock present in person or represented by proxy and entitled to vote at the Annual Meeting are not voted in favor of continuation of the Rights Agreement, the Rights will automatically terminate and the only right of the holders of Rights will be to receive the $0.0001 redemption price.

Until a Right is exercised, the holder thereof, as such, will have no rights as a stockholder of the Company, including, without limitation, the right to vote or to receive dividends. While the distribution of the Rights will not be taxable to stockholders or to the Company, stockholders may, depending upon the circumstances, recognize taxable income in the event that the Rights become exercisable for Common Stock (or other consideration) of the Company or for common stock of the acquiring company or in the event of the redemption of the Rights as set forth above.

Any of the provisions of the Rights Agreement may be amended by the Board prior to the Distribution Date. After the Distribution Date, the provisions of the Rights Agreement may be amended by the Board in order to cure any ambiguity, to make changes which do not adversely affect the interests of holders of Rights, or to shorten or lengthen any time period under the Rights Agreement. The foregoing notwithstanding, no amendment may be made at such time as the Rights are not redeemable.

A copy of the Rights Agreement has been filed by the Company with the Securities and Exchange Commission as an Exhibit to the Current Reports on Form 8-K on July 8, 2005 and July 10, 2008. A copy of the Rights Agreement is available free of charge from the Company. This summary description of the Rights does not purport to be complete and is qualified in its entirety by reference to the Rights Agreement, which is incorporated herein by reference.