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                                                                   EXHIBIT 10.12

                                    AMENDMENT

                                       TO

                  RSA SECURITY INC. DEFERRED COMPENSATION PLAN

WITNESSETH:

WHEREAS: RSA Security Inc. (the "Company") maintains the RSA Security Inc.
Deferred Compensation Plan (the "Plan"), a nonqualified deferred compensation
plan subject to the requirements of Section 409A of the Internal Revenue Code of
1986, as amended; and

WHEREAS, section 10.01 of the Plan permits the Company to modify, amend or
terminate the Plan; and

WHEREAS, proposed regulations, published October 4, 2005 under Internal Revenue
Code Section 409A ("IRC 409A"), require an amendment to the Plan no later than
December 31, 2005 in order to authorize the Plan Administrator to offer the
transition elections to participants described in IRS Notice 2005-1; and

WHEREAS, the Company wishes to amend the Plan, effective as of the dates
specified in IRS Notice 2005-1, to authorize the Plan Administrator to offer to
participants, in its discretion, the transition relief described in Notice
2005-1; and

WHEREAS, the Company wishes that the amendments below apply only to deferrals
and earnings on deferrals that are credited on and after January 1, 2005 (within
the meaning of Notice 2005-1 and proposed Treasury regulations).

NOW, THEREFORE:

     1. The Plan is amended by adding new Section 6.04, to read as follows:

     "6.04 2005 DEFERRAL ELECTIONS

     Notwithstanding any provisions in the Plan concerning timing of initial
     deferral elections to the contrary and pursuant to transition relief
     provided in Q&A 20 (a) of Notice 2005-1, so long as the deferrals of
     compensation otherwise comply with IRC 409A, participants may make or
     modify deferral elections with respect to compensation that relates all or
     in part to services performed on or before December 31, 2005, so long as:
     (i) the deferral election with respect to such compensation is properly
     filed with the plan administrator prior to March 15, 2005; and (ii) the
     amounts to which the deferral election relate have not been paid or become
     payable prior to the election."

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     2. The Plan is amended by adding new Section 8.11 to read as follows:

     "8.11 2005 DEFERRAL MODIFICATION/CANCELLATION/TERMINATION ELECTIONS

     Notwithstanding any provisions in the Plan to the contrary, pursuant to
     transition relief provided in Q&A 20 (b) of Notice 2005-1 and in accordance
     with procedures established by the plan administrator, a participant may,
     with respect to his or her accounts that are subject to Code Section 409A
     only: (i) elect to terminate, or partially terminate, participation in the
     plan and receive payment of that portion of his or her vested account
     balance payable under the Plan corresponding to the portion of the Plan to
     which the termination applies; or (ii) elect to cancel or reduce a deferral
     election with regard to amounts subject to IRC 409A. An election by a
     participant permitted in (i) or (ii) hereinabove, shall be made no later
     than December 31, 2005."

The foregoing amendments shall apply only to deferrals and earnings on deferrals
credited to Participant Accounts on and after January 1, 2005, as provided in
Notice 2005-1. Deferrals and earnings on deferrals credited prior to January 1,
2005 shall be governed by the terms of the Plan as in effect as of October 2,
2004. Except as amended hereby, the terms of the Plan, subject to operational
compliance with Notice 2005-1 and applicable Treasury regulations, remain in
full force and effect.

IN WITNESS WHEREOF: the Company has caused this Amendment to the Plan to be
executed by its duly authorized officer as of the Effective Date.

RSA Security Inc.


BY: /s/ Arthur W. Coviello, Jr.
    ---------------------------------
ITS: President and Chief Executive
     Officer