EXHIBIT 10.1
 
SUBSCRIPTION AGREEMENT

THIS SUBSCRIPTION AGREEMENT (this “Agreement”), is by and between American DG
Energy Inc., a Delaware corporation (the “Company”), and the subscriber
identified on the signature page below (the “Subscriber”).

The Company and the Subscriber hereby agree as follows:
 
1.           Purchase and Sale of Shares.
 
(a) Subject to the terms and conditions of this Agreement, at the First Closing
(as defined herein), the Company shall sell and issue to the Subscriber, and the
Subscriber shall purchase from the Company that number of shares of the
Company’s Common Stock set forth on the signature page at the per share purchase
price also specified therein.
 
(b) At the Second Closing (as defined herein), at the option of the Subscriber,
the Company shall sell and issue to the Subscriber, and the Subscriber shall
purchase from the Company, that number of shares of the Company’s Common Stock
set forth on the signature page at the per share purchase price also specified
therein. The shares sold at the First Closing and, if issued, the shares sold at
the Second Closing are referred to herein as the “Shares”.
 
 2.           Closings.  The Closings shall take place as follows:
 

(a) The first closing (the “First Closing”) of the sale and purchase of the
Shares pursuant to this Agreement is taking place contemporaneously with the
execution and delivery of this Agreement on the date hereof. At the First
Closing, the Subscriber is wiring to an account specified by the Company the
purchase price for the Shares being purchased at the First Closing. As soon as
practical after the First Closing, the Company will cause its transfer agent to
deliver to the Subscriber a certificate representing that number of Shares so
purchased, which shall be registered in the name of the Purchaser or its
nominee.

(b) The Subscriber shall indicate to the Company by written notice given no
later than December 15th, 2009, whether or not it elects that the second closing
under this Agreement (the “Second Closing”) shall occur. Such notice shall
specify a closing date for the Second Closing no more than 3 business days after
the delivery of such notice, or December 18th, 2009. At the Second Closing, the
Subscriber will wire to an account specified by the Company the purchase price
for the Shares being purchased at the Second Closing. As soon as practical after
the Second Closing, the Company will cause its transfer agent to deliver to the
Subscriber a certificate representing that number of Shares so purchased, which
shall be registered in the name of the Purchaser or its nominee.

(c) The First Closing and the Second Closing, if any, shall be collectively
referred to as the “Closings,” each may individually be referred to as a
“Closing” and the date of each Closing shall be referred to as a “Closing Date.”
All deliveries at each Closing shall take place by the electronic delivery, by
fax or email, of all closing documents.

(d)           In the event that the Subscriber shall notify the Company that it
elects that the Second Closing shall occur, the obligation of the Subscriber to
consummate the Second Closing shall be subject to the satisfaction, prior to or
at the Second Closing, of the following conditions:  (i) the representations and
warranties of the Company contained in this Agreement shall be true and correct
in all material respects on and as of the Second Closing Date as though such
warranties and representations were made at and as of such date; (ii) the
Company shall have performed and complied in all material respects with all
agreements, covenants and conditions contained in this Agreement which are
required to be performed or complied with by the Company prior to or at the
Closing; and (iii) there shall be no effective injunction, writ, preliminary
restraining order or any order of any nature issued by a court of competent
jurisdiction directing that the transactions provided for herein or any of them
not be consummated as herein provided.
 
American DG Energy Inc
Subscription Agreement Offering 2009
 
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(e)           In the event that the Subscriber shall notify the Company that it
elects that the Second Closing shall occur, the obligation of the Company to
consummate the Second Closing shall be subject to the satisfaction, prior to or
at the Second Closing, of the following conditions:  (i)  the representations
and warranties of the Subscriber contained in this Agreement shall be true on
and as of the Second Closing Date in all material respects as though such
warranties and representations were made at and as of such date; (ii) the
Subscriber shall have performed and complied in all material respects with all
agreements, covenants and conditions contained in this Agreement which are
required to be performed or complied with by it prior to or at the Second
Closing; and (iii) there shall be no effective injunction, writ, preliminary
restraining order or any order of any nature issued by a court of competent
jurisdiction directing that the transactions provided for herein or any of them
not be consummated as herein provided.

3.           Subscriber’s Representations and Warranties. The Subscriber hereby
represents and warrants to and agrees with the Company that:

(a)           Information on Company.  The Subscriber has been furnished with or
has had access at the EDGAR website of the U.S. Securities and Exchange
Commission (the “SEC”) to the Company’s Form 10-K for the year ended December
31, 2008, and all filings subsequently made by the Company with the SEC
(hereinafter referred to collectively as the “Reports”). In addition, the
Subscriber has received in writing from the Company such other information
concerning its operations, financial condition and other matters as the
Subscriber has requested in writing and considered all factors the Subscriber
deems material in deciding on the advisability of investing in the Shares.

(b)           Information on Subscriber.  The Subscriber was at the time it was
offered the Shares, is on the date hereof and will be on the Closing Date an
“accredited investor”, as such term is defined in Reg. D promulgated by the SEC
under the Securities Act, is experienced in investments and business matters,
has made investments of a speculative or high risk nature and has purchased
securities of publicly-owned companies in private placements in the past and,
together with its representatives and/or trustee, as applicable, has such
knowledge and experience in financial, tax and other business matters as to
enable the Subscriber to utilize the information made available by the Company
to evaluate the merits and risks of and to make an informed investment decision
with respect to the proposed purchase. The Subscriber has the authority and is
duly and legally qualified to purchase and own the Shares. The Subscriber is
able to bear the risk of such investment for an indefinite period and to afford
a complete loss thereof. The information set forth on the signature page
regarding the Subscriber is accurate. The Subscriber does not currently hold or
beneficially own any shares of the Company’s Common Stock other than as set
forth on the signature page. The Subscriber was not formed for the specific
purpose of acquiring the Shares and is not a registered broker-dealer or an
affiliate of a registered broker-dealer.

(c)           Purchase for Investment.  On the Closing Date, the Subscriber will
purchase the Shares as principal for its own account for investment and not with
a view to any sale of other transfer thereof in contravention of the Securities
Act.

(d)           Compliance with the Securities Act.  The Subscriber understands
and agrees that the Shares have not been registered under the Securities Act of
1933 (the “Securities Act”) or any applicable state securities laws by reason of
their issuance in a transaction that does not require registration under the
Securities Act (based in part on the accuracy of the representations and
warranties of Subscriber contained herein), and that such Shares must be held
indefinitely unless a subsequent disposition is registered under the Securities
Act or any applicable state securities laws or is exempt from such registration.
 
American DG Energy Inc
Subscription Agreement Offering 2009
 
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(e)           Restrictive Legend. The Shares may bear a customary restrictive
Securities Act legend in the form specified by the Company.

 (f)           Communication of Offer. The offer to sell the Shares was directly
communicated to the Subscriber by the Company. At no time was the Subscriber
presented with or solicited by any leaflet, newspaper or magazine article, radio
or television advertisement, or any other form of general advertising or
solicited or invited to attend a promotional meeting otherwise than in
connection and concurrently with such communicated offer.

(g)           Organization; Authority; Enforceability.  The Subscriber, if an
entity, is duly organized, validly existing and in good standing under the laws
of the jurisdiction of its organization (if such “good standing” concept is
recognized in such jurisdiction) with full right, corporate,  partnership or
trust power and authority to enter into and to consummate the transactions
contemplated by this Agreement. This Agreement and other agreements delivered
together with this Agreement or in connection herewith have been duly
authorized, executed and delivered by the Subscriber and are valid and binding
agreements enforceable in accordance with their terms, subject to bankruptcy,
insolvency, fraudulent transfer, reorganization, moratorium and similar laws of
general applicability relating to or affecting creditors’ rights generally and
to general principles of equity; and Subscriber has full corporate, partnership,
trust or similar power and authority necessary to enter into this Agreement and
such other agreements and to perform its obligations hereunder and under all
other agreements entered into by the Subscriber relating hereto.

(h)           Correctness of Representations. The Subscriber represents that the
foregoing representations and warranties are true and correct as of the date
hereof and, unless the Subscriber otherwise notifies the Company prior to the
Closing, shall be true and correct as of the Closing Date.

(i)           Survival. The foregoing representations and warranties shall
survive the applicable Closing Date for three years.

(j)           Restriction on Short Sales. The Subscriber agrees that, to the
extent required by law, it will not enter into or effect any short sale or other
hedging transaction with respect to the Company’s Common Stock.

(k)           Disclosure. The Subscriber acknowledges and agrees that the
Company does not make nor has made any representations or warranties with
respect to the Shares or the transactions contemplated hereby other than those
specifically set forth in Section 4 hereof.

4.           Company Representations and Warranties.  The Company represents and
warrants to and agrees with the Subscriber that on the date hereof:

(a)           Due Incorporation. The Company is a corporation duly organized,
validly existing and in good standing under the laws of the State of Delaware
and has the requisite corporate power to own its properties and to carry on its
business as now being conducted.

(b)           Outstanding Stock. All issued and outstanding shares of capital
stock of the Company have been duly authorized and validly issued and are fully
paid and non-assessable.

(c)           Authority; Enforceability.  The Company has full corporate power
and authority necessary to enter into and deliver this Agreement and to perform
its obligations thereunder. This Agreement has been duly authorized, executed
and delivered by the Company and is a valid and binding agreement enforceable
against the Company in accordance with its terms, subject to bankruptcy,
insolvency, fraudulent transfer, reorganization, moratorium and similar laws of
general applicability relating to or affecting creditors’ rights generally and
to general principles of equity.
 
American DG Energy Inc
Subscription Agreement Offering 2009
 
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(d)           Consents.  No consent, approval, authorization or order of any
court or governmental agency or body having jurisdiction over the Company is
required for the execution by the Company of this Agreement and compliance and
performance by the Company of its obligations hereunder, including, without
limitation, the issuance and sale of the Shares.

(e)           No Violation or Conflict.  Assuming the representations and
warranties of the Subscriber in Section 3 are true and correct, neither the
issuance and sale of the Shares nor the performance of the Company’s obligations
under this Agreement and all other agreements entered into by the Company
relating thereto by the Company will:

(i)           violate, conflict with, result in a breach of, or constitute a
default (or an event which with the giving of notice or the lapse of time or
both would be reasonably likely to constitute a default) under (A) the
certificate of incorporation of the Company, (B) to the Company’s knowledge, any
decree, judgment, order, law, treaty, rule, regulation or determination
applicable to the Company of any court or governmental agency or body having
jurisdiction over the Company or over the properties or assets of the Company,
(C) the terms of any bond, debenture, note or any other evidence of
indebtedness, or any agreement, stock option or other similar plan, indenture,
lease, mortgage, deed of trust or other instrument to which the Company is a
party, by which the Company is bound, or to which any of the properties of the
Company is subject, or (D) the terms of any “lock-up” or similar provision of
any underwriting or similar agreement to which the Company is a party except the
violation, conflict, breach, or default of which would not have a material
adverse effect on the business, operations or financial condition of the Company
and its subsidiaries taken as a whole (a “Material Adverse Effect”);

(ii)           result in the activation of any anti-dilution rights or a reset
or re-pricing of any debt or security instrument of any other creditor or equity
holder of the Company, nor result in the acceleration of the due date of any
borrowing of the Company; or

(iii)           result in the activation of any piggy-back registration rights
of any person or entity holding securities of the Company or having the right to
receive securities of the Company.

(f)           The Shares.  The Shares upon issuance in accordance with the terms
of this Agreement:

(i)           are, or will be, free and clear of any security interests, liens,
claims or other encumbrances, subject to restrictions upon transfer under the
Securities Act and any applicable state securities laws;

(ii)           will be duly and validly authorized, and on the date of issuance
of the Shares, the Shares will be duly and validly issued, fully paid and
nonassessable; and

(iii)           will not have been issued or sold in violation of any preemptive
or other similar rights of the holders of any securities of the Company.

 (g)           Litigation.  There is no pending or, to the best knowledge of the
Company, threatened action, suit, proceeding or investigation before any court,
governmental agency or body, or arbitrator having jurisdiction over the Company
that would affect the execution by the Company or the performance by the Company
of its obligations under this Agreement, and all other agreements entered into
by the Company relating hereto.  Except as disclosed in the Reports, there is no
pending or, to the best knowledge of the Company, basis for or threatened
action, suit, proceeding or investigation before any court or governmental
agency or body, which litigation if adversely determined could have a Material
Adverse Effect.

(h)           Reporting Company.  The Company is a publicly-held company subject
to reporting obligations pursuant to the Securities Exchange Act of 1934, as
amended (the “Exchange Act”) and its shares of Common Stock are registered
pursuant to Section 12(g) of the Exchange Act. The Company has timely filed all
reports and other materials required to be filed under the Exchange Act during
the preceding twelve months.

 
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(i)           Information Concerning the Company.  The Reports contain all
material information relating to the Company and its operations and financial
condition as of their respective dates that is required by the Exchange Act to
be disclosed therein.  Since the date of the financial statements included in
the Reports, there has been no Material Adverse Effect not disclosed in the
Reports. The Reports, at the time of filing, did not contain any untrue
statement of a material fact or omit to state a material fact required to be
stated therein or necessary to make the statements therein not misleading in
light of the circumstances when made.

 (j)           No Integrated Offering.  Neither the Company, nor any of its
affiliates, nor any person acting on its or their behalf, has directly or
indirectly made any offers or sales of any security or solicited any offers to
buy any security under circumstances that would cause the offer of the Shares
pursuant to this Agreement to be integrated with prior offerings by the Company
so as to invalidate any exemptions under the Securities Act for the offer and
sale of the Shares.

(k)           No General Solicitation.  Neither the Company, nor any of its
affiliates, nor to its knowledge, any person acting on its or their behalf, has
engaged in any form of general solicitation or general advertising (within the
meaning of Reg. D under the Securities Act) in connection with the offer or sale
of the Shares.

(l)           No Material Undisclosed Events or Circumstances.  Since the date
of the last Report filed under the Exchange Act, no event or circumstance has
occurred or exists with respect to the Company or its business, operations or
financial condition, that, under applicable law, rule or regulation, requires
the filing of a Report prior to the date hereof that has not been so filed.

(m)           Correctness of Representations.  The Company represents that the
foregoing representations and warranties are true and correct as of the date
hereof in all material respects, and, unless the Company otherwise notifies the
Subscriber prior to the Closing, shall be true and correct in all material
respects as of the Closing Date.

(n)           Survival.  The foregoing representations and warranties shall
survive the applicable Closing Date for a period of three years.

5.           Reg. D Offering.  The offer and issuance of the Shares to the
Subscriber is being made pursuant to the exemption from the registration
provisions of the Securities Act afforded by Section 4(2) or Section 4(6) of the
Securities Act and/or Rule 506 of Reg. D promulgated thereunder.

6.           Covenants of the Company.  The Company covenants and agrees with
the Subscriber as follows:

(a)           Exchange Act Filings.  The Company shall file a Form 8-K with the
SEC disclosing the transactions contemplated by this Agreement within the time
period specified therefor by the rules and regulations under the Exchange Act.
The Company agrees to file a Form D with respect to the Shares as required under
Reg. D.

(b)           Reporting Requirements.  Until all of the Shares have been resold
or transferred by the Subscriber, or, if earlier, two years after the applicable
Closing Date, the Company will use commercially reasonable best efforts (i) not
to take any action or file any document (whether or not permitted by the
Securities Act or the Exchange Act or the rules thereunder) to terminate or
suspend the registration of the shares of the Company’s Common Stock under the
Exchange Act and (ii) to continue the listing of the shares of the Company’s
Common stock on the Over-the-Counter Bulletin Board or other established trading
market.
 
American DG Energy Inc
Subscription Agreement Offering 2009

 
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7.           Registration Rights. The Company hereby grants the following
registration rights to holders of the Shares.

(a)           Registration Statement. The Company shall file with the SEC not
later than thirty (30) days after the Closing Date a “shelf” registration
statement on an appropriate form, or shall file with the SEC as soon as
practical an amendment to its currently filed shelf registration statement
(either the “Registration Statement”) covering the resale of the Shares and
shall use its commercially reasonable best efforts to cause the Registration
Statement to be declared effective as soon as practicable.

(b)           Registration Procedures. In connection with the Registration
Statement, the Company will:

(i)           prepare and file with the SEC such amendments and supplements to
the Registration Statement and the prospectus used in connection therewith as
may be necessary to keep such Registration Statement effective with respect to
the Subscriber until such time as all of the Shares owned by the Subscriber may
be resold without restriction under the Securities Act; and

(ii)           immediately notify the Subscriber when the prospectus included in
the Registration Statement is required to be delivered under the Securities Act,
of the happening of any event of which the Company has knowledge as a result of
which the prospectus contained in such Registration Statement, as then in
effect, includes an untrue statement of a material fact or omits to state a
material fact required to be stated therein or necessary to make the statements
therein not misleading in light of the circumstances then existing. If the
Company notifies the Subscriber to suspend the use of any prospectus until the
requisite changes to such prospectus have been made, then the Subscriber shall
suspend use of such prospectus.  In such event, the Company will use its
commercially reasonable efforts to update such prospectus as promptly as is
practicable.

(c)           Provision of Documents etc.  In connection with the Registration
Statement, the Subscriber will furnish to the Company in writing such
information and representation letters with respect to itself and the proposed
distribution by it as reasonably shall be necessary in order to assure
compliance with federal and applicable state securities laws. The Company may
require the Subscriber, upon five business days’ notice, to furnish to the
Company a certified statement as to, among other things, the number of  Shares
and the number of other shares of the Company’s Common Stock beneficially owned
by the Subscriber and the person that has voting and dispositive control over
such shares. The Subscriber covenants and agrees that it will comply with the
prospectus delivery requirements of the Securities Act, if applicable, in
connection with sales of Shares pursuant to the Registration Statement.

(d)           Expenses.  All expenses incurred by the Company in complying with
this section, including, without limitation, all registration and filing fees,
printing expenses, fees and disbursements of counsel and independent public
accountants for the Company, fees of transfer agents and registrars are called
“Registration Expenses.” All underwriting discounts and selling commissions
applicable to the sale of the Shares, including any fees and disbursements of
any counsel to the Subscriber, are called “Selling Expenses.” The Company will
pay all Registration Expenses in connection with the Registration Statement.
Selling Expenses in connection with the Registration Statement shall be borne by
the applicable Subscriber.

(e)           Indemnification and Contribution.

(i)           The Company will, to the extent permitted by law, indemnify and
hold harmless the Subscriber, each officer of the Subscriber, each director of
the Subscriber, and each other person, if any, who controls the Subscriber
within the meaning of the Securities Act, against any losses, claims, damages or
liabilities, joint or several, to which the Subscriber or such other person (a
“controlling person”) may become subject under the Securities Act or otherwise,
insofar as such losses, claims, damages or liabilities (or actions in respect
thereof) (“Claims”) arise out of or are based upon any untrue statement or
alleged untrue statement of any material fact contained in the Registration
Statement at the time of its effectiveness, any preliminary prospectus or final
prospectus contained therein, or any amendment or supplement thereof, or arise
out of or are based upon the omission or alleged omission to state therein a
material fact required to be stated therein or necessary to make the statements
therein not misleading in light of the circumstances when made, and will,
subject to the limitations herein, reimburse the Subscriber and each such
controlling person for any legal or other expenses reasonably incurred by them
in connection with investigating or defending any such Claim; provided, however,
that the Company shall not be liable to the Subscriber to the extent that any
Claim arises out of or is based upon an untrue statement or alleged untrue
statement or omission or alleged omission made in conformity with information
furnished by the Subscriber or any such controlling person in writing
specifically for use in the Registration Statement or related prospectus, as
amended or supplemented.
 
American DG Energy Inc
Subscription Agreement Offering 2009
 
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(ii)           The Subscriber will, to the extent permitted by law, indemnify
and hold harmless the Company, and each person, if any, who controls the Company
within the meaning of the Securities Act, each underwriter, each officer of the
Company who signs the Registration Statement and each director of the Company
against all Claims to which the Company or such officer, director, underwriter
or controlling person may become subject under the Securities Act or otherwise,
insofar as such Claims arise out of or are based upon any untrue statement or
alleged untrue statement of any material fact contained in the Registration
Statement, any preliminary prospectus or final prospectus contained therein, or
any amendment or supplement thereof, or the omission or alleged omission to
state therein a material fact required to be stated therein or necessary to make
the statements therein not misleading, and will reimburse the Company and each
such officer, director, underwriter and controlling person for any legal or
other expenses reasonably incurred by them in connection with investigating or
defending any such loss, claim, damage, liability or action, provided, however,
that the Subscriber will be liable hereunder in any such case if and only to the
extent that any such Claim arises out of or is based upon an untrue statement or
alleged untrue statement or omission or alleged omission made in reliance upon
and in conformity with information pertaining to the Subscriber, as such,
furnished in writing to the Company by the Subscriber specifically for use in
the Registration Statement or related prospectus, as amended or supplemented.

(iii)           Promptly after receipt by an indemnified party hereunder of
notice of the commencement of any action, such indemnified party shall, if a
claim in respect thereof is to be made against the indemnifying party hereunder,
notify the indemnifying party in writing thereof, but the omission so to notify
the indemnifying party shall not relieve it from any liability which it may have
to such indemnified party other than under this section and shall only relieve
it from any liability which it may have to such indemnified party under this
section except and only if and to the extent the indemnifying party is
materially prejudiced by such omission. In case any such action shall be brought
against any indemnified party and it shall notify the indemnifying party of the
commencement thereof, the indemnifying party shall be entitled to participate in
and, to the extent it shall wish, to assume and undertake the defense thereof
with counsel satisfactory to such indemnified party, and, after notice from the
indemnifying party to such indemnified party of its election so to assume and
undertake the defense thereof, the indemnifying party shall not be liable to
such indemnified party under this section for any legal expenses subsequently
incurred by such indemnified party in connection with the defense thereof other
than reasonable costs of investigation and of liaison with counsel so selected;
provided, however, that, if the defendants in any such action include both the
indemnified party and the indemnifying party and the indemnified party shall
have reasonably concluded that there may be reasonable defenses available to it
which are different from or additional to those available to the indemnifying
party or if the interests of the indemnified party reasonably may be deemed to
conflict with the interests of the indemnifying party, the indemnified parties,
as a group, shall have the right to select one separate counsel and to assume
such legal defenses and otherwise to participate in the defense of such action,
with the reasonable expenses and fees of such separate counsel and other
expenses related to such participation to be reimbursed by the indemnifying
party as incurred. The indemnifying party shall not be liable for any settlement
of any such proceeding affected without its written consent, which consent shall
not be unreasonably withheld.

(iv)           In order to provide for just and equitable contribution in the
event of joint liability under the Securities Act in any case in which either
(i) the Subscriber, or any controlling person of the Subscriber, makes a claim
for indemnification pursuant to this section but it is judicially determined (by
the entry of a final judgment or decree by a court of competent jurisdiction and
the expiration of time to appeal or the denial of the last right of appeal) that
such indemnification may not be enforced in such case notwithstanding the fact
that this section provides for indemnification in such case, or (ii)
contribution under the Securities Act may be required on the part of the
Subscriber or controlling person of the Subscriber in circumstances for which
indemnification is not provided under this section, then, and in each such case,
the Company and the Subscriber will contribute to the aggregate losses, claims,
damages or liabilities to which they may be subject (after contribution from
others) in a manner that reflects, as near as practicable, the economic effect
of the foregoing provisions of this section. Notwithstanding the foregoing, no
person or entity guilty of fraudulent misrepresentation (within the meaning of
Section 10(f) of the Securities Act) will be entitled to contribution from any
person or entity who was not guilty of such fraudulent misrepresentation.
 
American DG Energy Inc
Subscription Agreement Offering 2009
 
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(f)           Delivery of Unlegended Shares.

(i)           Within three business days (such business day, the “Unlegended
Shares Delivery Date”) after the business day on which the Company has received
(i) a notice that Shares have been sold either pursuant to, and in compliance
with, the Registration Statement or Rule 144 under the Securities Act and (ii)
in the case of sales under Rule 144, customary representation letters of the
Subscriber and Subscriber’s broker regarding compliance with the requirements of
Rule 144, the Company at its expense, (A) shall deliver the Shares so sold
without any restrictive legends relating to the Securities Act (the “Unlegended
Shares”); and (B) shall cause the transmission of the certificates representing
the Unlegended Shares together with a legended certificate representing the
balance of the unsold Shares, if any, to the Subscriber at the address specified
in the notice of sale, via express courier, by electronic transfer or otherwise
on or before the Unlegended Shares Delivery Date.  Transfer fees shall be the
responsibility of the Subscriber.

(ii)           In lieu of delivering physical certificates representing the
Unlegended Shares, if the Company’s transfer agent is participating in the
Depository Trust Company (“DTC”) Fast Automated Securities Transfer program,
upon request of the Subscriber, so long as the certificates therefor do not bear
a legend and the Subscriber is not obligated to return such certificate for the
placement of a legend thereon, the Company shall use its best efforts to cause
its transfer agent to electronically transmit the Unlegended Shares by crediting
the account of Subscriber’s broker with DTC through its Deposit/Withdrawal at
Custodian system.  Such delivery must be made on or before the Unlegended Shares
Delivery Date but is subject to the cooperation of the Subscriber’s broker (the
so-called DTC participant).

(iii)           The Subscriber agrees that the removal of the restrictive legend
from certificates representing the Shares as set forth in this section is
predicated upon the Company’s reliance that the Subscriber will sell any Shares
pursuant to either the registration requirements of the Securities Act,
including any applicable prospectus delivery requirements, or an exemption
therefrom.

8.           Miscellaneous.

(a)           Notices.  All notices, demands, requests, consents, approvals, and
other communications required or permitted hereunder shall be in writing and,
unless otherwise specified herein, shall be (i) personally served, (ii)
delivered by reputable overnight courier service with charges prepaid, or (iii)
transmitted by fax, addressed, if to the Company, to Chief Financial Officer,
American DG Energy Inc., 45 First Avenue, Waltham, MA 02451, fax: (781)
622-1027, and if to the Subscriber, to the Subscriber at the address set forth
on the signature pages hereto or to such other address as such party shall have
specified most recently by written notice.

(b)           Amendments; Waivers.  No provision of this Agreement may be waived
or amended except in a written instrument signed, in the case of an amendment,
by the Company and the Subscriber.  No waiver of any default with respect to any
provision, condition or requirement of this Agreement shall be deemed to be a
continuing waiver in the future or a waiver of any subsequent default or a
waiver of any other provision, condition or requirement hereof, nor shall any
delay or omission of either party to exercise any right hereunder in any manner
impair the exercise of any such right.
 
American DG Energy Inc
Subscription Agreement Offering 2009

 
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(c)           Legal Fees.   Each party shall pay its own legal fees and expenses
in connection with the transactions contemplated by this Agreement.

(d)           Entire Agreement; Assignment.  This Agreement and other documents
delivered in connection herewith represent the entire agreement between the
parties hereto with respect to the subject matter hereof.  Neither the Company
nor the Subscriber have relied on any representations not contained or referred
to in this Agreement and the documents delivered herewith.  No right or
obligation of either party shall be assigned by that party without prior notice
to and the written consent of the other party.

(e)            Counterparts/Execution.  This Agreement may be executed in any
number of counterparts and by the different signatories hereto on separate
counterparts, each of which, when so executed, shall be deemed an original, but
all such counterparts shall constitute but one and the same
instrument.  Signatures to this Agreement may be delivered by fax or by
scan/email.

(f)           Law Governing this Agreement.  This Agreement shall be governed by
and construed in accordance with the laws of the State of Delaware without
regard to principles of conflicts of laws. Any action brought by either party
against the other concerning the transactions contemplated by this Agreement
shall be brought only in the state courts of Massachusetts or in the federal
courts located in Massachusetts.  The parties and the individuals executing this
Agreement and other agreements referred to herein or delivered in connection
herewith on behalf of the Company agree to submit to the jurisdiction of such
courts and waive trial by jury.

(g)           Equitable Adjustment.   The Shares and the purchase price Per
Share shall be equitably adjusted to offset the effect of stock splits, stock
dividends, and distributions of property or equity interests of the Company to
its shareholders prior to the Second Closing.
 
American DG Energy Inc
Subscription Agreement Offering 2009

 
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[Signature page immediately follows.]
Signature Page and Questionnaire – First Closing July 2009

The Subscriber hereby executes this Subscription Agreement. By initialing the
appropriate space below, the Subscriber hereby represents that the Subscriber
is:

 
(initials)
 
a corporation, a business trust, or a partnership, not formed for the specific
purpose of acquiring the Shares, with total assets in excess of $5,000,000.
     
 
(initials)
 
a natural person whose individual net worth, or joint net worth with his or her
spouse, exceeds $1,000,000.
     
 
(initials)
 
a natural person who had an individual income in excess of $200,000 in each of
the two most recent years, or joint income with his or her spouse in excess of
$300,000 in each of those years, and has a reasonable expectation of reaching
the same income level in the current year.
     
 
(initials)
 
a trust with total assets in excess of $5,000,000, not formed for the specific
purpose of acquiring the Shares.
     
 
(initials)
 
an entity in which all of the equity owners fall within one of the categories
set forth above.

U.S. $2.10
   
Share purchase price at First Closing é
 
Subscriber’s name é
     
Number of Shares purchased at First Closing é
 
$
 
Subscriber’s signature é
 
 
Aggregate dollar amount being purchased at
First Closing é
 
 
 
 
Address of the Subscriber ê
 
 
           
 
Agreed and Accepted - American DG Energy Inc.:
 
 
Phone number:
 
By:
 
 
Email address:
 
Date:
 
 
U.S. Tax ID # (if any):
     

 
American DG Energy Inc
Subscription Agreement Offering 2009
 
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Signature Page and Questionnaire – Second Closing December 2009

The Subscriber hereby executes this Subscription Agreement. By initialing the
appropriate space below, the Subscriber hereby represents that the Subscriber
is:

 
(initials)
 
a corporation, a business trust, or a partnership, not formed for the specific
purpose of acquiring the Shares, with total assets in excess of $5,000,000.
     
 
(initials)
 
a natural person whose individual net worth, or joint net worth with his or her
spouse, exceeds $1,000,000.
     
 
(initials)
 
a natural person who had an individual income in excess of $200,000 in each of
the two most recent years, or joint income with his or her spouse in excess of
$300,000 in each of those years, and has a reasonable expectation of reaching
the same income level in the current year.
     
 
(initials)
 
a trust with total assets in excess of $5,000,000, not formed for the specific
purpose of acquiring the Shares.
     
 
(initials)
 
an entity in which all of the equity owners fall within one of the categories
set forth above.

U.S. $3.10
   
Share purchase price at Second Closing é
 
Subscriber’s name é
     
Number of Shares purchased, at the Subscriber’s option, at Second Closing é
 
$
 
Subscriber’s signature é
 
Aggregate dollar amount being purchased, at the Subscriber’s option, at Second
Closing é
 
 
 
 
Address of the Subscriber ê
 
 
           
 
Agreed and Accepted - American DG Energy Inc.:
 
 
Phone number:
 
By:
 
 
Email address:
 
Date:
 
 
U.S. Tax ID # (if any):
     

American DG Energy Inc
Subscription Agreement Offering 2009
 
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