Exhibit 10.12

JOINDER AGREEMENT

THIS JOINDER IN MASTER SECURITY AGREEMENT, EQUITY PLEDGE AGREEMENT and GUARANTY
(this “Joinder”) is executed as of July 24, 2009 by PetroAlgae Inc., a Delaware
corporation (“Joining Party”), PA LLC (f/k/a PetroAlgae, LLC) (“PA”) and
PetroTech Holdings, Corp. (“Holdings”) and delivered to LV Administrative
Services, Inc. as administrative and collateral agent (the “Agent”) for Valens
U.S. SPV I, LLC (“Valens” and together with Agent, individually, each a
“Creditor Party” and collectively, the “Creditor Parties”). Except as otherwise
defined herein, terms used herein and defined in the Loan Documents (as defined
below), as applicable, shall be used herein as therein defined.

W I T N E S S E T H:

WHEREAS, PA and the Agent, have entered into a Master Security Agreement dated
August 8, 2008 and amended and restated as of the date hereof (as further
amended, restated, modified and/or supplemented from time to time, the “Master
Security Agreement”);

WHEREAS, Holdings and the Agent, have entered into an Equity Pledge Agreement,
dated as of August 15, 2009 (as amended, modified or supplemented from time to
time, the “Pledge Agreement”);

WHEREAS, Holdings has executed a Guaranty dated August 15, 2009 in favor of the
Agent (as amended, modified and/or supplemented from time to time, the
“Guaranty” and together with the Master Security Agreement and the Pledge
Agreement, the “Loan Documents”);

WHEREAS, the Joining Party shall become (i) an Assignor under the Master
Security Agreement, (ii) a Pledgor under the Pledge Agreement and (iii) a
Guarantor under the Guaranty;

NOW, THEREFORE, in consideration of the foregoing and other benefits accruing to
the Joining Party, the receipt and sufficiency of which are hereby acknowledged,
the Joining Party hereby makes the following representations and warranties to
the Creditor Parties and hereby covenants and agrees with the Creditor Parties
as follows:

NOW, THEREFORE, the Joining Party agrees as follows:

1. By this Joinder, the Joining Party becomes (i) an Assignor for all purposes
under the Master Security Agreement, (ii) a Pledgor for all purposes under the
Pledge Agreement and (iii) a Guarantor for all purposes under the Guaranty.

2. PA and the Joining Party agrees that, upon the Joining Party’s execution
hereof, the Joining Party will become an Assignor under, and as defined in, the
Master Security Agreement, and will be bound by all terms, conditions and duties

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applicable to an Assignor under the Master Security Agreement. Without
limitation of the foregoing and in furtherance thereof, as security for the due
and punctual payment of the Obligations (as defined in the Master Security
Agreement), PA and the Joining Party hereby pledges, hypothecates, assigns,
transfers, sets over and delivers to the Agent for the benefit of the Creditor
Parties and grants to the Agent for the benefit of Valens a security interest in
all Collateral (as defined in the Master Security Agreement), if any, now owned
or, to the extent provided in the Master Security Agreement, hereafter acquired
by it.

3. Holdings and the Joining Party agree that, upon the Joining Party’s execution
hereof, the Joining Party will become a Pledgor under, and as defined in, the
Pledge Agreement, and will be bound by all terms, conditions and duties
applicable to a Pledgor under the Pledge Agreement. Without limitation of the
foregoing and in furtherance thereof, as security for the due and punctual
payment of the Secured Obligations (as defined in the Pledge Agreement),
Holdings and the Joining Party hereby pledges, hypothecates, assigns, transfers,
sets over and delivers to the Agent for the benefit of the Creditor Parties and
grants to the Agent for the benefit of Valens a security interest in all
Collateral (as defined in the Pledge Agreement), if any, now owned or, to the
extent provided in the Pledge Agreement, hereafter acquired by it.

4. The Joining Party agrees that, upon its execution hereof, it will become a
Guarantor under the Guaranty with respect to all Obligations (as defined in the
Guaranty), and will be bound by all terms, conditions and duties applicable to a
Guarantor under the Guaranty for the benefit of Valens. Without limitation of
the foregoing, and in furtherance thereof, each of Holdings and the Joining
Party unconditionally and irrevocably, guarantees the due and punctual payment
and performance of all Obligations (on the same basis as the other Guarantors
under the Guaranty).

5. In connection with the grants by the Companies and the Joining Party,
pursuant to paragraphs 2 and 3 above, of a security interest in all of its
right, title and interest in the Collateral (as defined in each of the Master
Security Agreement and the Equity Pledge Agreement) in favor of the Agent for
the benefit of Valens, the Joining Party (i) agrees to deliver to the Agent,
together with the delivery of this Joinder, each of the items specified in
Section 4 of the Equity Pledge Agreement, (ii) agrees to execute (if necessary)
and deliver to the Agent such financing statements, in form acceptable to the
Agent, as the Agent may request or as are necessary or desirable in the opinion
of the Agent to establish and maintain a valid, enforceable, first priority
perfected security interest in the Collateral (as defined in each of the Master
Security Agreement and the Equity Pledge Agreement) owned by the Joining Party,
(iii) authorizes the Agent to file any such financing statements without the
signature of the Joining Party where permitted by law (such authorization
includes a description of the Collateral as “all assets and all personal
property, whether now owned and/or hereafter acquired” of the Joining Party (or
any substantially similar variation thereof)) and (iv) agrees to execute and
deliver to the Agent assignments of United States trademarks, patents and
copyrights (and the respective applications therefor) to the extent requested by
the Agent.

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6. Without limiting the foregoing, the Joining Party and the Companies, hereby
makes and undertakes, as the case may be, each covenant, representation and
warranty made by, and as (i) each Guarantor pursuant to the Guaranty, (ii) each
Assignor pursuant to the Master Security Agreement and, (iii) each Pledgor
pursuant to the Equity Pledge Agreement in each case as of the date hereof
(except to the extent any such representation or warranty relates solely to an
earlier date in which case such representation and warranty shall be true and
correct as of such earlier date), and agrees to be bound by all covenants,
agreements and obligations of a Guarantor, Assignor ,and Pledgor pursuant to the
Guaranty, Master Security Agreement and, Equity Pledge, respectively, and all
other related agreements to which it is or becomes a party.

7. Schedule A to the Pledge Agreement is hereby amended by supplementing such
Schedule with the information contained on Schedule A attached hereto as Annex
I. In addition, Schedule A to the Master Security Agreement is hereby amended by
supplementing such Schedule with the information contained on Schedule A
attached hereto as Annex II.

8. This Joinder shall be binding upon the parties hereto and their respective
successors and permitted assigns and shall inure to the benefit of and be
enforceable by each of the parties hereto and its successors and permitted
assigns, provided, however, PA nor the Joining Party may assign any of its
rights, obligations or interest hereunder without the prior written consent of
the Creditor Parties. THIS JOINDER SHALL BE CONSTRUED AND ENFORCED IN ACCORDANCE
WITH AND GOVERNED BY THE LAW OF THE STATE OF NEW YORK. This Joinder may be
executed in any number of counterparts, each of which shall be an original, but
all of which shall constitute one instrument. In the event that any provision of
this Joinder shall prove to be invalid or unenforceable, such provision shall be
deemed to be severable from the other provisions of this Joinder which shall
remain binding on all parties hereto.

9. The effective date of this Joinder is July 24, 2009.

IN WITNESS WHEREOF, the Joining Party, PA, Holdings and the Creditor Parties
have caused this Joinder to be duly executed as of the date first above written.

 

PETROALGAE INC. By:   /s/ David P. Szostak   Name: David P. Szostak   Title:  
President

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PA LLC By:   /s/ Ottmar Dippold   Name: Ottmar Dippold   Title:   CEO PETROTECH
HOLDINGS, CORP. By:   /s/ Patrick Regan   Name: Patrick Regan   Title:  
Authorized Signatory

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Accepted and Acknowledged by:

LV ADMINISTRATIVE SERVICES, INC.,

as Agent

By:   /s/ Patrick Regan   Name: Patrick Regan   Title:   Authorized Signatory
VALENS U.S. SPV I, LLC

By: Valens Capital Management, LLC,

its investment manager

By:   /s/ Patrick Regan   Name: Patrick Regan   Title:   Authorized Signatory

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ANNEX I

SCHEDULE 1

Equity Interests Owned by Pledgor

 

Pledgor

   Issuer    Certificate
Number    Equity Interests    Units/Shares

PetroTech Holdings, Corp.

   PetroAlgae Inc.    1116    Common Stock    100,000,000 Shares

PetroAlgae Inc.

   PA LLC    2    Membership Interests    19,000,000 Class A Units

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000231    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000232    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000233    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000234    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000235    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000236    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000237    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000238    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000239    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000240    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000241    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000242    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000243    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000244    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000245    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000246    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000247    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000248    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000249    Common Stock    200,000 Shares

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PetroTech Holdings, Corp.

   TyraTech, Inc.    00000250    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000251    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000252    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000253    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000254    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000255    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000256    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000257    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000258    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000259    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000260    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000261    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000262    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000263    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000264    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000265    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000266    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000267    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000268    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000269    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000270    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000271    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000272    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000273    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000274    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000275    Common Stock    200,000 Shares

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PetroTech Holdings, Corp.

   TyraTech, Inc.    00000276    Common Stock    200,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000277    Common Stock    254,090 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000280    Common Stock    250,000 Shares

PetroTech Holdings, Corp.

   TyraTech, Inc.    00000281    Common Stock    250,000 Shares

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ANNEX II

SCHEDULE A

 

Entity

   Jurisdiction of Formation    Organizational
Identification Number

PA LLC

   Delaware    4224141

PETROALGAE INC.

   Delaware    4421184