NOTICE OF GUARANTEED DELIVERY FOR TENDER OF OUTSTANDING 12% SENIOR SUBORDINATED NOTES DUE 2009 IN EXCHANGE FOR 12% SENIOR SUBORDINATED NOTES DUE 2009 REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OF ANTEON CORPORATION Registered holders of outstanding 12% Senior Subordinated Notes due 2009 (the "Initial Notes") who wish to tender their Initial Notes in exchange for a like principal amount of 12% Senior Subordinated Notes due 2009 (the "Exchange Notes") and whose Initial Notes are not immediately available or who cannot deliver their Initial Notes and Letter of Transmittal (and any other documents required by the Letter of Transmittal) to IBJ Whitehall Bank & Trust Company (the "Exchange Agent") prior to the Expiration Date, may use this Notice of Guaranteed Delivery or one substantially equivalent hereto. This Notice of Guaranteed Delivery may be delivered by hand or sent by facsimile transmission (receipt confirmed by telephone and an original delivered by guaranteed overnight courier) or letter to the Exchange Agent. See "The Exchange Offer--Procedures for Tendering Initial Notes" in the Prospectus. The Exchange Agent for the Exchange Offer is: IBJ WHITEHALL BANK & TRUST COMPANY BY REGISTERED OR CERTIFIED MAIL: IBJ Whitehall Bank & Trust Company P.O. Box 84 Bowling Green Station New York, NY 10274-0084 Attn: Reorganization Operations Department BY HAND OR OVERNIGHT DELIVERY: IBJ Whitehall Bank & Trust Company One State Street New York, NY 10004 Attn: Securities Processing Window, Subcellar One, (SC-1) BY FACSIMILE FOR ELIGIBLE INSTITUTIONS: (212) 858-2611 FOR CONFIRMATION AND/OR INFORMATION CALL: (212) 858-2103 Delivery of this Notice of Guaranteed Delivery to an address other than as set forth above or transmission of instructions via a facsimile transmission to a number other than as set forth above will not constitute a valid delivery. This Notice of Guaranteed Delivery is not to be used to guarantee signatures. If a signature on a Letter of Transmittal is required to be guaranteed by an Eligible Institution (as defined in the Prospectus), such signature guarantee must appear in the applicable space provided on the Letter of Transmittal for Guarantee of Signatures. Ladies and Gentlemen: The undersigned hereby tenders the principal amount of Initial Notes indicated below, upon the terms and subject to the conditions contained in the Prospectus dated , 1999 of Anteon Corporation, receipt of which is hereby acknowledged. DESCRIPTION OF SECURITIES TENDERED NAME AND ADDRESS OF REGISTERED HOLDER AS IT APPEARS ON THE 12% SENIOR SUBORDINATED CERTIFICATE NUMBER(S) AGGREGATE PRINCIPAL PRINCIPAL AMOUNT OF NOTES DUE 2009 ("INITIAL OF AMOUNT REPRESENTED BY INITIAL NOTES NOTES") (PLEASE PRINT) INITIAL NOTES TENDERED INITIAL NOTES TENDERED - ---------------------------------- ----------------- ---------------- --------------- - ---------------------------------- ----------------- ---------------- --------------- - ---------------------------------- ----------------- ---------------- --------------- - ---------------------------------- ----------------- ---------------- --------------- - ---------------------------------- ----------------- ---------------- --------------- 2 THE FOLLOWING GUARANTEE MUST BE COMPLETED GUARANTEE OF DELIVERY (NOT TO BE USED FOR SIGNATURE GUARANTEE) The undersigned, a firm that is a member of a registered national securities exchange or a member of the National Association of Securities Dealers, Inc. or a commercial bank or trust company having an office, branch, agency or correspondent in the United States, hereby guarantees to deliver to the Exchange Agent at one of its addresses set forth above, the certificates representing the Initial Notes, together with a properly completed and duly executed Letter of Transmittal (or facsimile thereof), with any required signature guarantees, and any other documents required by the Letter of Transmittal within three New York Stock Exchange, Inc. trading days after the date of execution of this Notice of Guaranteed Delivery. NAME OF FIRM: __________________________________________________________________ (AUTHORIZED SIGNATURE) ADDRESS: ________________________________TITLE: ________________________________ ______________________________________________ NAME: ___________________________ (ZIP CODE) (PLEASE TYPE OR PRINT) AREA CODE AND TELEPHONE NUMBER: _____________________ DATE: ____________________ NOTE: DO NOT SEND INITIAL NOTES WITH THIS NOTICE OF GUARANTEED DELIVERY. INITIAL NOTES SHOULD BE SENT WITH YOUR LETTER OF TRANSMITTAL. 3