Exhibit 10.15

PREFERRED STOCKHOLDERS STANDBY AGREEMENT

THIS PREFERRED STOCKHOLDERS STANDBY AGREEMENT (“Agreement”), dated as of
April 14, 2008, entered into between Wells Fargo Foothill, Inc. (formerly known
as Foothill Capital Corporation), as agent (“Agent”) for itself and for the
Lenders (defined below), and the party identified on the signature page hereto
as the “Preferred Stockholder” (the “Preferred Stockholder”).

W I T N E S S E T H

WHEREAS, Preferred Stockholder is financially interested in Telos Corporation, a
Maryland corporation (“Company”), in that Company has issued certain of its
Series A-1 Redeemable Preferred Stock (“Series A-1”) and its Series A-2
Redeemable Preferred Stock (“Series A-2”; Series A-1 and Series A-2 are
collectively the Preferred Stock”) to Preferred Stockholder;

WHEREAS, Company is indebted to Agent and Lenders in connection with the
advances of monies and other financial arrangements by Agent and Lenders to
Company; and

WHEREAS, such advances of monies and other financial arrangements are evidenced
by various agreements, instruments and documents, including, without limitation,
that certain Amended and Restated Loan and Security Agreement dated as of
April 3, 2008, but effective as of March 31, 2008, between Company, certain
financial institutions from time to time party thereto as lenders (“Lenders”)
and Agent (the “Loan Agreement”);

NOW, THEREFORE, for good and valuable consideration, the receipt and sufficiency
of which are hereby acknowledged by hereby agree with Agent as hereinafter set
forth.

1. Agreement. Preferred Stockholder will not ask, demand, sue for, take or
receive from Company or any other party, by setoff or in any other manner, the
whole or any part of any indebtedness, obligations and liabilities which may now
or hereafter be owing by Company, or any successor or assign of Company,
including, without limitation, a receiver, trustee or debtor in possession (the
term “Company” hereinafter shall include any such successor and assign of
Company), to the Preferred Stockholder in respect of the Preferred Stock
(including, without limitation, any payments in respect of dividends or
redemptions in respect of the Preferred Stock), unless and until all
obligations, liabilities, and indebtedness of Company to Agent and Lenders,
whether now existing or hereafter arising directly between Company and Agent or
any Lender, or acquired outright, conditionally or as collateral security from
another by Agent or any Lender, shall have been fully paid and satisfied in cash
with interest, including, without limitation, any interest accruing after the
commencement of insolvency proceedings with respect to Company, whether or not
such interest is allowed as a claim in such proceeding (all such obligations,
indebtedness and

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liabilities of Company to Agent and each Lender being hereinafter referred to as
the “Senior Debt”) and all financing arrangements between Company, Agent and
Lenders have been terminated.

2. Priority of Agent and Lenders. In the event of any distribution, division or
application, partial or complete, voluntary or involuntary, by operation of law
or otherwise, of all or any part of the assets of Company or the proceeds
thereof to the creditors of Company or readjustment of the obligations and
indebtedness of Company, whether by reason of liquidation, bankruptcy,
arrangement, receivership, assignment for the benefit of creditors or any other
action or proceeding involving the readjustment of all or any part of the
Preferred Stock, or the application of the assets of Company to the payment or
liquidation thereof, or upon the dissolution, liquidation, cessation or other
winding up of Company’s business, or upon the sale of all or substantially all
of Company’s assets, then, and in any such event, (i) Agent, for the benefit of
itself and Lenders, shall be entitled to receive payment in cash in full of any
and all of the Senior Debt then owing prior to the payment of all or any part of
the Preferred Stock and (ii) any payment or distribution of any kind or
character, whether in cash, securities or other property, which shall be payable
or deliverable upon or with respect to any or all of the Preferred Stock shall
be paid or delivered directly to Agent for application on any of the Senior
Debt, due or not due, until such Senior Debt shall have first been fully paid
and satisfied in cash.

3. Payments Received by Preferred Stockholder. Should any payment, distribution,
security or instrument, or any proceeds thereof, be received by the Preferred
Stockholder upon or with respect to the Preferred Stock prior to the
satisfaction of all of the Senior Debt in cash and termination of all financing
arrangements between Company, Agent and Lenders, the Preferred Stockholder shall
receive and hold the same in trust, as trustee, for the benefit of Agent and
Lenders and shall forthwith deliver the same to Agent in precisely the form
received (except for the endorsement or assignment by the Preferred Stockholder
where necessary), for application on any of the Senior Debt, due or not due,
and, until so delivered, the same shall be held in trust by the Preferred
Stockholder as the property of Agent.

4. Instrument Legend; Amendments. Any instrument or certificate evidencing any
of the Preferred Stock, or any portion thereof, will be inscribed with a legend
conspicuously indicating that payment thereof is subject to the terms of this
Agreement, and a copy thereof will be delivered to Agent.

5. Extension of Maturity of Preferred Stock. Preferred Stockholder hereby agrees
that the redemption date of the Preferred Stock shall be extended until
December 31, 2011.

6. GOVERNING LAW; CONSENT TO JURISDICTION; WAIVERS. THIS AGREEMENT SHALL BE
DEEMED TO HAVE BEEN MADE IN THE STATE OF ILLINOIS AND SHALL BE INTERPRETED IN
ACCORDANCE WITH THE INTERNAL LAWS OF ILLINOIS AND NOT THE CONFLICT OF LAWS RULES
OF THE STATE

 

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OF ILLINOIS GOVERNING CONTRACTS TO BE PERFORMED ENTIRELY WITHIN SUCH STATE.
PREFERRED STOCKHOLDER HEREBY AGREES TO THE EXCLUSIVE JURISDICTION OF ANY STATE
OR FEDERAL COURT LOCATED WITHIN THE COUNTY OF COOK, STATE OF ILLINOIS OR, AT THE
SOLE OPTION OF AGENT, IN ANY OTHER COURT IN WHICH AGENT SHALL INITIATE LEGAL OR
EQUITABLE PROCEEDINGS AND WHICH HAS SUBJECT MATTER JURISDICTION. OVER THE MATTER
IN CONTROVERSY. PREFERRED STOCKHOLDER WAIVES ANY OBJECTION OF FORUM NON
CONVENIENS AND VENUE. AGENT AND PREFERRED STOCKHOLDER EACH HEREBY WAIVE THE
RIGHT TO TRIAL BY JURY IN ANY ACTION OR PROCEEDING BASED UPON, ARISING OUT OF,
OR IN ANY WAY RELATING TO THIS AGREEMENT, WHETHER SOUNDING IN CONTRACT OR TORT
OR OTHERWISE.

7. Notices. Any notice required hereunder shall be in writing and addressed to
the party to be notified as follows:

 

If to the Agent, at:   

Wells Fargo Foothill, Inc.

One Boston Place, 18th Floor

Boston, Massachusetts 02108

Attn: Technology Finance Division Manager

Fax No. (617) 523-1697

If to the Preferred Stockholder, at:   

North Atlantic Smaller Companies Investment

Trust PLC

c/o North Atlantic Value LLP

Ground Floor, Ryder Court

14 Ryder Street

London SW1Y 6QB

England

or to such other address as each party may designate for itself by notice.
Notice shall be deemed to have been duly given (i) if delivered personally or
otherwise actually received, (ii) if sent by overnight delivery service,
(iii) if mailed by first class United States mail, postage prepaid, registered
or certified, with return receipt requested or (iv) if sent by telex with telex
confirmation of receipt (with duplicate notice sent by United States mail as
provided above). Notice mailed as provided in clause (iii) above shall be
effective upon the expiration of three (3) business days after its deposit in
the United States mail. Notice given in any other manner described in this
paragraph shall be effective upon receipt by the addressee thereof; provided,
however, that if any notice is tendered to an addressee and delivery thereof is
refused by such addressee, such notice shall be effective upon such tender.

 

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IN WITNESS WHEREOF, this Agreement has been signed as of the date first above
written.

 

AGENT: WELLS FARGO FOOTHILL, INC., as Agent for Lenders By  

LOGO [g25920ex10_15pg004.jpg]

Its  

V.P.

PREFERRED STOCKHOLDER: NORTH ATLANTIC SMALLER COMPANIES INVESTMENT TRUST PLC By
 

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Its  

CEO

 

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