Exhibit 5
September 17, 2008
Capstone Turbine Corporation
21211 Nordhoff Street
Chatsworth, CA 91311
Re: Registration Statement on Form S-3
Ladies and Gentlemen:
We have acted as counsel to Capstone Turbine Corporation, a Delaware corporation (the
“Company”), in connection with the Registration Statement on Form S-3 (the “Registration
Statement”) to be filed by the Company with the Securities and Exchange Commission relating to the
registration of up to $7,398,229 in aggregate amount of shares of Common Stock, $0.001 par value,
and certain related rights to purchase Preferred Shares (the “Common Shares”), warrants to purchase
Common Shares (the “Common Share Warrants,”) and Common Shares issuable on exercise of such Common
Share Warrants (the “Warrant Shares”, and together with the Common Shares and the Common Share
Warrants, the “Securities”), all of which Securities may be offered and sold by the Company from
time to time as set forth in the prospectus which forms a part of the Registration Statement (the
“Prospectus”), and as to be set forth in one or more supplements to the Prospectus (each, a
“Prospectus Supplement”).
In connection with this opinion, we have examined and relied upon such records, documents and
other instruments as in our judgment are necessary or appropriate in order to express the opinions
hereinafter set forth and have assumed the genuineness of all signatures, the authenticity of all
documents submitted to us as originals and the conformity to original documents of all documents
submitted to us as certified or photostatic copies.
In rendering the following opinion, we state that we are not admitted to practice in any state
other than the State of Tennessee, and we express no opinion as to the laws of any jurisdiction
other than the State of Tennessee, the General Corporation Law of the State of Delaware and the
federal law of the United States to the extent specifically referred to herein. All opinions
expressed are as of the date hereof except where expressly stated otherwise.
Based upon, subject to and limited by the foregoing, we are of the opinion that, as of the
date hereof:
(1) Upon issuance of the Common Shares against payment therefor in accordance with the terms
of any applicable placement agency agreement and as contemplated by the Registration Statement
and/or the applicable Prospectus Supplement, the Common Shares will be duly authorized and validly
issued, fully paid and non-assessable by the Company.
(2) When the Common Share Warrants have been duly executed and delivered on behalf of the
Company against payment therefor in accordance with the terms of any applicable placement agency
agreement and as contemplated by the Registration Statement and/or the applicable Prospectus
Supplement, the Common Share Warrants will be duly authorized, executed and delivered, valid,
binding and enforceable.
(3) Upon the exercise of the Common Share Warrants, the Warrant Shares issued against payment
therefor in accordance with the terms of the Common Share Warrants will be duly authorized and
validly issued, fully paid and non-assessable by the Company.
We assume no obligation to advise you of any changes in the foregoing subsequent to the
delivery of this opinion letter. This opinion letter has been prepared solely for your use in
connection with the transmitting for filing of the Registration Statement on the date of this
opinion letter and should not be quoted in whole or in part or otherwise be referred to, nor filed
with or furnished to any governmental agency or other person or entity, without the prior written
consent of this firm.
We hereby consent to the filing of this opinion letter as Exhibit 5 to the Registration
Statement and further consent to the reference to this firm under the caption “Legal Matters” in
the Prospectus constituting a part of the Registration Statement. In giving this consent, we do not
thereby admit that this firm is an “expert” within the meaning of the Act.
Very truly yours,
/s/ WALLER LANSDEN DORTCH & DAVIS, LLP