EXHIBIT 10.11

EXECUTION COPY

GUARANTY

THIS GUARANTY (this “Guaranty”) is made as of the 8th day of December, 2006 by
and among HOPKINS CAPITAL GROUP II, LLC (“Hopkins”), FRANCIS E. O’DONNELL, JR.
(“O’Donnell”), KATHLEEN M. O’DONNELL, TRUSTEE OF THE FRANCIS E. O’DONNELL, JR.
IRREVOCABLE TRUST (the “O’Donnell Trust”), DENNIS L. RYLL (“Ryll”), RONALD E.
OSMAN (“Osman”), ALAN M. PEARCE (“Pearce”), STEVEN ARIKIAN (“Arikian”), STEVEN
J. STOGEL (“Stogel”), DONALD L. FERGUSON (“Ferguson”) and DONALD L. FERGUSON,
TRUSTEE OF THE DONALD L. FERGUSON REVOCABLE TRUST (the “Ferguson Trust”)
(O’Donnell, the O’Donnell Trust, Ryll, Osman, Pearce, Arikian, Stogel, Ferguson
and the Ferguson Trust, whether one or more, hereinafter called “Individual
Guarantor” in the singular), BIOVEST INTERNATIONAL, INC., a Delaware corporation
(“Biovest”) (Biovest and the Individual Guarantors, whether one or more,
hereinafter called “Guarantor” in the singular) to and for the benefit of U.S.
BANCORP COMMUNITY INVESTMENT CORPORATION, a Delaware corporation (“USB”), and
with respect to the guaranty set forth in Section 2B hereof, ST. LOUIS NEW
MARKETS TAX CREDIT FUND-II, LLC, a Missouri limited liability company (the
“CDE”), and its managing member, ST. LOUIS DEVELOPMENT CORPORATION, a Missouri
nonprofit corporation (“SLD”).

RECITALS

WHEREAS, the CDE has received a sub-allocation of New Markets Tax Credits (the
“Tax Credits”) under Section 45D of the Internal Revenue Code of 1986, as
amended, and the rules an regulations promulgated thereunder (collectively, the
“Code”).

WHEREAS, AutovaxID Investment LLC, a Missouri limited liability company (the
“Fund”) has contributed equity to the CDE (the “QEI Contribution”), which equity
is expected to constitute a “qualified equity investment” (“QEI”) under the New
Markets Tax Credit program authorized by Section 45D of the Code (the “NMTC
Program”).

WHEREAS, the QEI Contribution is being funded in part with the proceeds of
equity contributed to the Fund by USB. The proceeds of the QEI Contribution will
be used by the CDE to fund a loan to AutovaxID, Inc., a Florida corporation
(“Borrower”), in the original principal amount of $7,700,000 (the “CDE Loan”),
which is expected to constitute a “qualified low-income community investment”
under the NMTC Program.

WHEREAS, the Tax Credits claimable by USB in connection with the QEI
Contribution have allowed USB to provide the QEI Contribution to the CDE on more
favorable terms, which in turn has allowed the CDE to provide the CDE Loan to
Borrower on more favorable terms and, as a result, Borrower believes that it
shall substantially benefit, directly or indirectly, from the making of the QEI
Contribution.

WHEREAS, the Borrower is primarily engaged in the business of manufacturing
automated cell production instruments within a United States population census
tract number which constitutes a Low-Income Community under the NMTC Program,
and the proceeds of the CDE Loan will be used to finance certain activities of
Borrower associated with the foregoing activities.

WHEREAS, in connection with the foregoing and concurrently herewith, USB and
Borrower have entered into that certain Tax Credit Reimbursement and Indemnity
Agreement (the “Indemnity”).

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WHEREAS, each Guarantor is an owner (directly or indirectly) of Borrower, USB’s
acquisition of a membership interest in the Fund is of material benefit to each
Guarantor, and without this Guaranty, USB would not acquire a membership
interest in, or make its contribution to, the Fund.

WHEREAS, to induce USB to acquire a membership interest in, and make its equity
contribution to, the Fund, each Guarantor has agreed to enter into this
Guaranty.

NOW, THEREFORE, in consideration of the foregoing, and for other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto, intending to be legally bound hereby, each
hereby covenants and agrees to and for the benefit of USB as follows:

1. Notwithstanding anything to the contrary set forth herein, as used herein,
the terms “several”, “severally”, “joint and several” or “jointly and severally”
as they relate to the Guaranteed Indemnity Obligations hereunder mean:

(A) The obligation of Hopkins, O’Donnell and the O’Donnell Trust, collectively,
as to any liability covered hereby shall be several and not joint and several
with the liability of O’Donnell and the O’Donnell Trust, collectively, not to
exceed 25.84% of any such liability for a maximum aggregate liability of
$1,150,000, and as limited hereby may be enforced at the option of USB against
each Guarantor of Guaranteed Indemnity Obligations severally;

(B) The obligation of Ryll as to any liability covered hereby shall be several
and not joint and several with the liability of Ryll not to exceed 22.47% of any
such liability for a maximum aggregate liability of $1,000,000, and as limited
hereby may be enforced at the option of USB against each Guarantor of Guaranteed
Indemnity Obligations severally;

(C) The obligation of Osman as to any liability covered hereby shall be several
and not joint and several with the liability of Osman not to exceed 22.47% of
any such liability for a maximum aggregate liability of $1,000,000, and as
limited hereby may be enforced at the option of USB against each Guarantor of
Guaranteed Indemnity Obligations severally;

(D) The obligation of Pearce as to any liability covered hereby shall be several
and not joint and several with the liability of Pearce not to exceed 11.24% of
any such liability for a maximum aggregate liability of $500,000, and as limited
hereby may be enforced at the option of USB against each Guarantor of Guaranteed
Indemnity Obligations severally;

(E) The obligation of Arikian as to any liability covered hereby shall be
several and not joint and several with the liability of Arikian not to exceed
1.12% of any such liability for a maximum aggregate liability of $50,000, and as
limited hereby may be enforced at the option of USB against each Guarantor of
Guaranteed Indemnity Obligations severally;

(F) The obligation of Stogel as to any liability covered hereby shall be several
and not joint and several with the liability of Pearce not to exceed 5.62% of
any such liability for a maximum aggregate liability of $250,000, and as limited
hereby may be enforced at the option of USB against each Guarantor of Guaranteed
Indemnity Obligations severally;

(G) The obligation of Ferguson and the Ferguson Trust, collectively, as to any
liability covered hereby shall be several and not joint and several with the
liability of Ferguson and the Ferguson Trust, collectively. not to exceed 11.24%
of any such liability

 

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for a maximum aggregate liability of $500,000, and as limited hereby may be
enforced at the option of USB against each Guarantor of Guaranteed Indemnity
Obligations severally;

(H) Biovest shall be jointly and severally liable for all of the Guaranteed
Obligations hereunder.

2. A. Each Individual Guarantor severally (as more particularly defined and
limited in maximum and percentage liability in Section 1 hereof) and Biovest
jointly and severally absolutely, unconditionally, and irrevocably guarantees
the full and prompt payment of any and all amounts which may become payable by
Borrower under the Indemnity (the “Guaranteed Indemnity Obligations”); provided,
however, that for purpose of determining the Guaranteed Indemnity Obligations
guaranteed by the Individual Guarantors, and for such purpose only, the Minimum
Return Shortfall shall be determined: (i) as if the internal rate of return
anticipated by the Investor, as reflected in the Financial Forecast, was an
internal rate of return calculated without inclusion of any deductions of the
Fund attributable to interest accruals in excess of payments, and (ii) without
reference to any actual deductions taken by the Fund attributable to interest
accruals in excess of payments. The terms “Minimum Return Shortfall,” “Investor”
and “Financial Forecast” shall all have the meaning set forth in the Indemnity.
Each Individual Guarantor severally (as more particularly defined and limited in
maximum liability in Section 1 hereof) and absolutely, unconditionally, and
irrevocably hereby also agrees to pay all reasonable costs, expenses, damages
and attorneys’ fees paid or incurred by USB, the CDE and SLD in endeavoring to
collect the Guaranteed Indemnity Obligations or in enforcing this Guaranty
against such Individual Guarantor; provided, however, in no event shall any
Individual Guarantor be required to pay any amounts required pursuant to the
foregoing provisions of this sentence in excess of such Individual Guarantor’s
maximum aggregate liability listed in Section 1 hereof. Biovest jointly and
severally absolutely, unconditionally, and irrevocably hereby also agrees to pay
all reasonable costs, expenses, damages and attorneys’ fees paid or incurred by
USB, the CDE and SLD in endeavoring to collect the Guaranteed Indemnity
Obligations or the Guaranteed Loan Obligations or in enforcing this Guaranty.

B. Biovest absolutely, unconditionally, and irrevocably guarantees the full and
prompt payment of any and all obligations of Borrower on the CDE Loan, together
with any Expenses (as such term is defined in the Operating Agreement of the CDE
), as may be payable by Borrower to the CDE or the Fund pursuant to such
Operating Agreement (the “Guaranteed Loan Obligations”, together with the
Guaranteed Indemnity Obligations, the “Guaranteed Obligations”), and Biovest
agrees to pay all reasonable costs, expenses, and attorneys’ fees paid or
incurred by USB and the CDE in enforcing this Guaranty.

3. This Guaranty is an absolute, unconditional, and continuing guaranty of
payment and performance of the Guaranteed Obligations and shall continue to be
in force and be binding upon each Guarantor until all of the Guaranteed
Obligations are irrevocably and indefeasibly satisfied or paid in full. This
Guaranty is an agreement of payment and performance and not merely of
collection.

4. Each Guarantor waives any and all defenses, claims, setoffs, and discharges
of Borrower, or any other obligor, pertaining to the Guaranteed Indemnity
Obligations or the Guaranteed Loan Obligations, as applicable, except the
defense of discharge by payment in full. Without limiting the generality of the
foregoing, each Guarantor will not assert, plead, or enforce against USB, the
CDE or SLD any defense available to Borrower of waiver, release, discharge, or
disallowance in bankruptcy, statute of limitations, res judicata, statute of
frauds, anti-deficiency statute, fraud, incapacity, minority, usury, illegality
or unenforceability which may be available to Borrower or any other person
liable in respect of any of the Guaranteed Obligations. The liability of each
Guarantor shall not be affected or impaired by any voluntary or involuntary
liquidation, dissolution, sale, or other disposition of all or substantially all
of the assets, marshalling of assets and liabilities, receivership, insolvency,
bankruptcy, assignment for the benefit of creditors, reorganization,
arrangement, composition or readjustment of, or other similar event or
proceeding affecting Borrower or any Guarantor or any of their respective
assets.

 

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Each Guarantor also waives promptness, diligence, and notice with respect to any
Guaranteed Obligations, any change of the time, manner, or place of payment or
other term of the Guaranteed Obligations, any exchange, release or
non-perfection of any collateral securing payment of any Guaranteed Obligations,
and any requirement that USB, the CDE or SLD, as applicable, exhaust any right
or take any action against the Borrower or any collateral security.

5. Each Guarantor waives presentment, demand for payment, notice of dishonor or
nonpayment, and protest of any instrument evidencing the Guaranteed Obligations.

6. If any payment applied by Borrower to the Guaranteed Obligations is
thereafter set aside, recovered, rescinded, or required to be returned for any
reason (including, without limitation, the bankruptcy, insolvency, or
reorganization of any Guarantor or any other obligor), the Guaranteed
Obligations to which such payment was applied shall for the purpose of this
Guaranty be deemed to have continued in existence notwithstanding such
application, and this Guaranty shall be enforceable as to such Guaranteed
Obligations as fully as if such application had never been made.

7. This Guaranty shall be effective upon delivery to USB, the CDE and SLD,
without further act, condition, or acceptance by USB or the CDE, shall be
binding upon each Guarantor and the successors and assigns of each Guarantor and
shall inure to the benefit of USB, the CDE, SLD, and their participants and
their successors, and to the benefit of any assignees of the Guaranty and their
successors.

8. Each Guarantor represents and warrants as follows:

(a) to the extent Guarantor is an entity, Guarantor is duly organized and
validly existing under the laws of the state in which it is organized;

(b) it has all requisite power and authority to execute, deliver, and perform
this Guaranty;

(c) to the extent Guarantor is an entity, its execution, delivery, and
performance of this Guaranty have been duly authorized by all necessary action
on its part;

(d) it has executed and delivered this Guaranty and this Guaranty is the legal,
valid, and binding obligation of Guarantor, enforceable against it in accordance
with its terms subject to the effect of applicable bankruptcy, insolvency,
reorganization, moratorium, fraudulent conveyance or similar laws relating to or
affecting creditors’ rights generally, and to the effect of general principles
of equity (regardless of whether considered in a proceeding in equity or at
law);

(e) neither the execution nor delivery of this Guaranty nor compliance with or
fulfillment of the terms, conditions, and provisions hereof, conflicts with,
results in a material breach or violation of the terms, conditions, or
provisions of, or constitutes a material default, an event of default, or an
event creating rights of acceleration, termination, or cancellation, or a loss
of rights under (i) the organizational documents of Guarantor, to the extent
Guarantor is an entity, (ii) any judgment, decree, order, contract, agreement,
indenture, instrument, note, mortgage, lease, governmental permit, or other
authorization, right, restriction, or obligation to which Guarantor is party or
any of its property is subject or by which Guarantor is bound, or (iii) any
federal, state, or local law, statute, ordinance, rule, or regulation applicable
to Guarantor;

(f) no consent, authorization, approval, order, license, certificate, or permit
or act of or from, or declaration of filing with, any governmental authority or
any party to any contract, agreement, instrument, lease, or license to which
Guarantor is a party or by which Guarantor is bound, is required for the
execution, delivery, performance, or compliance with the terms hereof by
Guarantor, except as have been obtained as required prior to the date hereof;

(g) there is no pending, or to the best of its knowledge, threatened, litigation
against Guarantor in any court or before any commission or regulatory body,
whether federal, state, or local, which challenges the validity or
enforceability of this Guaranty;

 

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(h) it is not insolvent within the meaning of applicable state laws and federal
laws relating generally to bankruptcy, insolvency, or reorganization or relief
of debtors; and

(i) the financial statements for Guarantor which have been presented to USB, the
CDE and SLD in connection with the transactions contemplated herein are true and
correct and fairly present the financial condition of Guarantor for the period
covered thereby; there have been no materially adverse changes in Guarantor’s
financial condition since the date(s) thereof; and Guarantor has not entered
into any commitments or contracts which are not reflected therein which may have
a materially adverse effect upon Guarantor’s financial condition, business or
operations.

9. All notices, approvals, requests, and demands to be made hereunder to any
party hereto shall be made in writing and addressed to the address set forth
below and shall be given by either of the following means:

(a) personal delivery or by prepaid courier, or express delivery service
(including, but not limited to, Federal Express, Express Mail, or United Parcel
Service); or

(b) registered United States mail, return receipt requested, and postage
prepaid.

A party’s address may be changed by notice to the other parties given in the
same manner as provided above. Any notice, demand, or request sent pursuant to
clause (a) shall be deemed received upon such delivery and, if sent pursuant to
clause (b), shall be deemed received five (5) days following deposit in the
mail.

 

  Biovest:   Biovest International, Inc.     324 S. Hyde Park Avenue     Suite
350     Tampa, Florida 33606   Hopkins:   Hopkins Capital Group II, LLC     c/o
Francis E. O’Donnell, Jr., M.D.     709 The Hamptons Lane     Town and Country,
MO 63017   O’Donnell:   Francis E. O’Donnell, Jr., M.D.     709 The Hamptons
Lane     Town and Country, MO 63017   O’Donnell Trust:   The Francis E.
O’Donnell, Jr. Irrevocable Trust     c/o Kathleen M. O’Donnell, Trustee     3101
N. Central     Suite 700     Phoenix, AZ 85012   Ryll:   Dennis L. Ryll     2595
Red Springs Drive     Las Vegas, NV 89135   Osman:   Ronald E. Osman     1602 W.
Kimmel St.     Marion, IL 62959   Pearce:   Alan M. Pearce     165 South Orange
Ave.     Newark, NJ 07103

 

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  Arikian:   Steven R. Arikian, M.D.     151 Beach 147th     Nepentist, NY 11694
  Stogel:   Steven J. Stogel     7777 Bonhomme     Suite 1210     St. Louis, MO
63105   Ferguson:   Donald L. Ferguson     11477 Olde Cabin Rd. Ste 110     St.
Louis, MO 63141   Ferguson Trust:   Donald L. Ferguson Revocable Trust     11477
Olde Cabin Rd. Ste 110     St. Louis, MO 63141   USB:   US Bancorp Community
Development Corporation     Attention: Darren Van’t Hof     1307 Washington
Avenue, Suite 300     St. Louis, Missouri 63103     Facsimile: (314) 418-0899  
  Telephone: (314) 418-0890   With a copy to:   Sonnenschein Nath & Rosenthal,
LLP     7800 Sears Tower     Chicago, Illinois 60606     Attention: Scott A.
Lindquist, Esq.     Telephone: (312) 876-8970     Facsimile: (312) 876-7934  
CDE:   St. Louis New Markets Tax Credit Fund-II, LLC     1015 Locust Street,
Suite 1200     St. Louis, MO 63101     Attention: Rodney Crim     Phone: (314)
622-3400     Facsimile: (314) 259-3442   With copy to:   Bryan Cave LLP     One
Metropolitan Square     211 North Broadway, Suite 3600     St. Louis, MO
63102-2750     Attention: Mary Gassmann Reichert, Esquire     Phone: (314)
259-2188     Facsimile: (314) 259-2020   SLD:   St. Louis Development
Corporation     1015 Locust Street, Suite 1200     St. Louis, MO 63101    
Attention: Rodney Crim     Phone: (314) 622-3400     Facsimile: (314) 259-3442

 

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  With copy to:        Bryan Cave LLP          One Metropolitan Square     
    211 North Broadway, Suite 3600          St. Louis, MO 63102-2750     
    Attention: Mary Gassmann Reichert, Esquire          Phone: (314) 259-2188  
       Facsimile: (314) 259-2020

10. No transfer or assignment by any of USB, the CDE, SLD or any Guarantor of
any of its rights hereunder (whether by operation of laws or otherwise) shall
relieve the transferor or assignor of any of its obligations hereunder.

11. In all respects, including, without limitation, matter of construction and
performance of this Guaranty and the obligations arising hereunder, this
Guaranty shall be governed by, and construed in accordance with the internal
laws of the State of Delaware applicable to contracts and obligations made in
such state and any applicable laws of the United States of America.

12. If any term or provisions of this Guaranty or the application thereof to any
person or circumstances shall, to any extent, be invalid or unenforceable, the
remainder of this Guaranty, or the application of such term or provision to
persons or circumstances other than those as to which it is held invalid or
unenforceable, shall not be affected thereby, and each term and provision of
this Guaranty shall be valid and enforced to the fullest extent permitted by
law.

13. The waiver of any provision of this Guaranty by USB, the CDE or SLD, as
applicable, shall constitute a waiver of this provision on that occasion only,
and shall not constitute a waiver of any other provision of this Guaranty, or
that provision with respect to any other occasion. No waiver of any provision of
this Guaranty by USB, the CDE or SLD, as applicable, shall be deemed effective
unless contained in a writing signed by it.

14. Where two or more persons or entities have executed this Guaranty, unless
the context clearly indicates otherwise, all references herein to “Guarantor”
shall mean the guarantors hereunder or either or any of them. All of the
obligations and liability of said guarantors hereunder shall be several or joint
and several (as further described in Section 1 of this Guaranty) and shall only
apply to a Guarantor to the extent described in Section 2 of this Guaranty. Suit
may be brought against said Guarantors, severally or jointly and severally (as
further described in Section 1 of this Guaranty), or against any one or more of
them, less than all, without impairing the rights of USB, the CDE and SLD
against the other or others of said Guarantors; and USB, the CDE or SLD, as
applicable, may compound with any one or more of said Guarantors for such sums
or sum as it may see fit and/or release such of said Guarantors from all further
liability to USB, the CDE and/or SLD, as applicable, for such indebtedness
without impairing the right of USB, the CDE or SLD, as applicable, to demand and
collect the balance of such indebtedness from the other or others of said
Guarantors not so compounded with or released; but it is agreed among said
Guarantors themselves, however, that such compounding and release shall not
impair the rights of said Guarantors as among themselves.

15. Except as otherwise provided herein, the rights of USB, the CDE and SLD are
cumulative and shall not be exhausted by its exercise of any of its rights
hereunder or otherwise against Guarantor or by any number of successive actions
until and unless all Indebtedness has been paid and each of the obligations of
Guarantor hereunder has been performed.

16. This Guaranty may only be modified, waived, altered or amended by a written
instrument or instruments executed by the party against which enforcement of
said action is asserted. Any alleged modification, waiver, alteration or
amendment which is not so documented shall not be effective as to any party.

 

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17. This Guaranty may be executed in any number of counterparts with the same
effect as if all parties hereto had signed the same document. All such
counterparts shall be construed together and shall constitute one instrument,
but in making proof hereof it shall only be necessary to produce one such
counterpart.

[Remainder of Page Intentionally Left Blank]

 

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IN WITNESS WHEREOF, this Guaranty has been duly executed and delivered by each
Guarantor as of the date first above written.

 

BIOVEST INTERNATIONAL, INC. By:  

/s/ Steven Arikian

Name:   Steven Arikian, M.D. Title:   Chairman & CEO HOPKINS CAPITAL GROUP II,
LLC By:  

/s/ Francis E. O’Donnell

  Francis E. O’Donnell Title:   Managing Partner  

/s/ Francis E. O’Donnell

  Francis E. O’Donnell, Jr.

FRANCIS E. O’DONNELL, JR.

IRREVOCABLE TRUST

By:  

/s/ Kathleen M. O’Donnell, Trustee

  Kathleen M. O’Donnell   Trustee

/s/ Dennis L. Ryll

Dennis L. Ryll

/s/ Ronald E. Osman

Ronald E. Osman

/s/ Alan M. Pearce

Alan M. Pearce

/s/ Steven R. Arikian

Steven R. Arikian

/s/ Steven J. Stogel

Steven J. Stogel

/s/ Donald L. Ferguson

Donald L. Ferguson DONALD L. FERGUSON REVOCABLE TRUST By:  

/s/ Donald L. Ferguson

  Donald L. Ferguson   Trustee

 

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