Document:

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                                                                   EXHIBIT 10.21

                               Warren V. Musser

October 4, 2000, as amended as of November 8, 2000

Safeguard Scientifics, Inc.
435 Devon Park Drive
Wayne, PA  19087

Ladies and Gentlemen:

This letter (the "Letter") was delivered to you in connection with the guaranty
delivered on the 4th day of October, 2000 by Safeguard Scientifics, Inc. (the
"Company") (such guaranty or any replacement thereof from the Company or any
affiliate of the Company referred to herein as the "Guaranty"), which Guaranty
relates to certain obligations to Legg Mason Wood Walker ("Legg Mason") arising
under the Warren V. Musser Foundation Inc Legg Mason Account (Number
[INTENTIONALLY OMITTED]) (the "Foundation Account") and the Warren V. Musser
Legg Mason Account (Number [INTENTIONALLY OMITTED]) (the "Musser Account," and
together with the Foundation Account, the "Accounts"). This Letter is being
amended in connection with the loan to you by the Company of an aggregate of
$10,000,000 made on October 18, 2000 (the "Loan")

In consideration of the Company's entering into the Guaranty and the extension
of the Loan, I hereby agree as follows:

     1.   I hereby irrevocably, unconditionally and absolutely agree to pay to
the Company, its successors and assigns all sums due or becoming due under the
Guaranty, including without limitation any amounts paid by the Company to Legg
Mason relating to the Accounts ("Reimbursement Payments"). My obligation to make
Reimbursement Payments to the Company is a continuing obligation and shall
remain in full force and effect and shall be binding upon me until the written
release of the Guaranty. This repayment obligation shall be in addition to and
not in substitution for any subrogation right the Company may have in connection
with the Guaranty. Any payment due hereunder and not made immediately following
demand therefor by the Company shall bear interest at a rate per annum equal to
the prime rate as set forth in The Wall Street Journal (the "Prime Rate") plus
                               -----------------------
2% payable on demand (determined on the basis of a 360-day year) from the date
of such demand until payment in full. My obligation under this paragraph to make
Reimbursement Payments shall be absolute and unconditional under any and all
circumstances whatsoever including, without limitation, the following
circumstances: (i) any lack of validity or enforceability of the Guaranty or any
other related documents; (ii) the amendment or waiver of or any consent to or
departure from the Guaranty; (iii) the existence of any claim, set-off, defense
or other rights which I may have at any time against the Company or any other
person or entity, whether in connection with this Letter, any related documents
or any unrelated transactions; and (iv) any other circumstance or happening
whatsoever, whether or not similar to any of the foregoing.
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     2.   I hereby agree to grant to the Company, to secure my obligations under
this Letter and under the Loan, at any time as the Company requests in its sole
discretion, a lien and security interest in any and all assets now owned or
hereafter acquired by me (which security interest shall be a first priority
interest subject only to such interests as exist on the date hereof), provided,
however that the grant of such a lien or security interest shall not apply to
any particular asset of mine if the grant of a lien or security interest in such
asset is prohibited by, or would otherwise constitute an event of default under,
any agreement with a third party lender to which I am a party or by which my
assets are bound; provided further, however, that at the Company's request I
will use my reasonable best efforts to obtain permission to grant liens on such
assets from such lenders to secure my obligations under this Letter and under
the Loan. I shall, at my expense, promptly execute and deliver all instruments
and documents and take all action that may be necessary or desirable, or that
the Company may request in its sole discretion, in order to grant, perfect or
protect any security interest granted to the Company including the actions set
forth in paragraph 7 below. All liens or security interests on my assets as of
the date of the amendment to this Letter are either fully described in the
financial disclosures I have provided to the Company or will provide to the
Company within two business days of the date hereof.

     3.   I hereby agree to reimburse the Company for any liabilities, losses,
claims, damages, actions, suits, proceedings, demands, fines, penalties,
assessments, adjustments, settlement payments, deficiencies, costs and expenses
(including, without limitation, reasonable attorneys' fees and expenses)
suffered, sustained, incurred or paid by the Company in connection with,
resulting from or arising directly or indirectly out of or incurred in entering
into and/or implementing or enforcing the Guaranty, the Loan and/or this Letter.

     4.   Without the prior written consent of the President or Chief Financial
Officer of the Company, I shall not dispose of any assets of the Accounts
(except to the extent that the assets disposed of are applied to the repayment
of the margin loans in the Accounts and do not involve the disposition of
Safeguard common stock or Internet Capital Group common stock unless such sale
is approved by the President or Chief Financial Officer of the Company) or incur
any additional indebtedness relating to the Accounts  or any other indebtedness
for borrowed money (including without limitation margin loans in the Accounts or
in any other accounts as to which the Accounts are contingently liable).
Subject to the rights of any senior creditors, with a senior lien on such assets
I agree to use the proceeds of all other assets sold by me (whether or not
pledged to secure my obligations under this Letter) to repay my obligations to
the Company set forth herein and relating to the Loan, provided, however, that I
shall be entitled to retain a portion of such proceeds equal to my reasonable
and good faith estimate of all taxes I will owe in connection with the
disposition of such assets based upon my overall tax position and taking into
account losses which are available to offset such taxes.

     5.   I shall prepare and submit promptly, but in any event not later than
November 14, 2000, to the appropriate special committee of the Board of
Directors of the Company a financial plan which describes in reasonably specific
detail the actions I will use my reasonable best efforts to take to eliminate
the Guaranty and to repay the Loan as promptly as practicable which plan shall
be reasonably acceptable to the special committee and shall provide that a
substantial amount of the Loan shall be repaid and a substantial portion of the
Company's liability under the Guaranty be reduced by December 31, 2000 (a
"Repayment Plan").  Notwithstanding anything to

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the contrary set forth herein, I will take such actions as are necessary to
repay the Loan and obtain the release of the Company from the Guaranty not later
than March 15, 2000. The failure to make such repayment and obtain such release
shall be a default hereunder.

     6.   From and after the date of this letter, I shall use my reasonable best
efforts to promptly put in place such alternative arrangements to release the
Company from its obligations under the Guaranty and to repay the Loan, including
securing a replacement guaranty for the obligations under the Accounts, infusing
additional capital in the Accounts, disposing of securities in the Accounts,
disposing of other assets in which I have an ownership interest and applying the
net proceeds of such dispositions in accordance with paragraph 4, or taking any
other action or entering into such other arrangements with a third party, in
each case as the Company may reasonably direct from time to time.

     7.   I shall promptly use my reasonable best efforts to sell the property
located at 304 Vassar Street, Cambridge, Massachusetts (the "Vassar Property")
on or before December 31, 2000 and cause all net proceeds of the sale to be
applied in accordance with paragraph 4. I agree to provide the Company with
weekly progress reports on the sale of the Vassar Property, and if such sale is
not made by December 31, 2000 to use my best efforts to get permission from the
current mortgagor to grant to the Company a mortgage on such property and
following obtaining such permission to grant the Company a lien on the Vassar
Property. Other than a mortgage to the Company, I agree not to grant any other
liens on the Vassar Property and to keep it free and clear of all liens not
existing on the date hereof or relating to real property taxes which are not yet
due or are being contested in good faith. Should the Company consent to any
refinancing of the Vassar Property, all proceeds shall be applied in accordance
with paragraph 4.

The undertakings and obligations set forth in this letter are intended to be
legally binding on me and my heirs and assigns, and may not be altered or
amended except by written instrument signed by the President of the Company
after due authorization from the Company's Board of Directors.

I hereby waive (i) any and all notices whatsoever with respect to this letter or
any of my obligations to the Company relating to the Guaranty, and (ii) the
defenses of diligence, presentment for payment and protest, demand or extensions
of time for payment.

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This letter amends and restates in its entirety the letter I delivered to the
Company on October 4, 2000 and shall be governed by, and construed, interpreted
and enforced in accordance with the laws of the Commonwealth of Pennsylvania.
By signing below, the Company agrees that copies of all communications to me
regarding this letter, the Guaranty, the Loan and Repayment Plan shall be
directed to my counsel, Morgan R. Jones, Esq., Drinker Biddle & Reath LLP, One
Logan Square, 18th & Cherry Streets, Philadelphia, PA  19103.

Very truly yours,

/s/ WARREN V. MUSSER

Warren V. Musser
Acknowledged and Accepted by
Safeguard Scientifics, Inc.

By:  /s/ HARRY WALLAESA
     --------------------
Name: Harry Wallaesa
Title: President

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                                                                   EXHIBIT 10.22

                       ASSUMPTION OF GUARANTY OF ACCOUNT

                                                       Dated:  November 13, 2000

To:  Legg Mason Wood Walker, Incorporated

1.    Safeguard Scientifics, Inc. ("Safeguard") has entered into that certain
      Guaranty of Account with Legg Mason Wood Walker, Incorporated ("Legg
      Mason"), dated October 4, 2000 (the "Guaranty"), with respect to the
      "guaranteed accounts" as defined in the Guaranty. In reliance upon the
      representations, warranties and covenants herein contained, effective as
      of October 4, 2000, Safeguard desires to be released from, and Legg Mason
      hereby releases Safeguard from, all liability under the Guaranty. In
      exchange therefor, and in consideration in part of the transaction
      described in the first sentence of Section 2(d) hereof, Safeguard's
      indirect wholly-owned subsidiary, Bonfield Insurance, Ltd., a British
      Virgin Islands corporation ("Bonfield"), desires to, and hereby does,
      effective as of October 4, 2000, assume all obligations of Safeguard under
      the Guaranty in all respects with the same effect as though all references
      in the Guaranty to "Safeguard" or "Guarantor" were deemed to refer to
      Bonfield, and Legg Mason hereby accepts such assumption.

2.    Safeguard and Bonfield hereby represents and warrants, jointly and
      severally, to Legg Mason the following:

      (a)  Organization. Safeguard is a corporation duly organized, validly
           ------------
           existing and in good standing under the laws of the Commonwealth of
           Pennsylvania, having all requisite corporate power and authority to
           perform its obligations under the Guaranty and this Agreement.
           Bonfield was formed in August 2000 and is a corporation duly
           organized, validly existing and in good standing under the laws of
           the British Virgin Islands, having all requisite corporate power and
           authority to perform its obligations under the Guaranty and this
           Agreement. Safeguard owns, directly or indirectly, all of the issued
           and outstanding capital stock of Bonfield, and will continue to do so
           throughout the life of the Guaranty.

      (b)  Authority and Binding Effect. Each of Safeguard and Bonfield has full
           ----------------------------
           power and authority to execute, deliver and perform the Guaranty and
           this Agreement, and has taken all actions necessary to secure all
           approvals required in connection therewith. The execution, delivery
           and performance of the Guaranty and this Agreement have been duly
           authorized by all necessary corporation action on the part of
           Safeguard and Bonfield. This Agreement constitutes the legal, valid
           and binding obligation of Safeguard and Bonfield, enforceable against
           it in accordance with its terms.

      (c)  Non-Contravention. Neither the execution and delivery of this
           -----------------
           Agreement by Safeguard or Bonfield, nor of the Guaranty by Bonfield,
           will contravene or violate any law, rule, regulation or court order
           which is applicable to Safeguard or Bonfield, or the charter
           documents of Safeguard or Bonfield, or will result in a default under
           any contract to which Safeguard or Bonfield is a party or by which it
           is otherwise bound.
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      (d)  Net Assets. Contemporaneously with the execution and delivery hereof,
           ----------
           Safeguard sold to Bonfield Safeguard's interest in Legg Mason Account
           No. [INTENTIONALLY OMITTED] in exchange for the transfer by Bonfield
           to Safeguard of Bonfield's interest in Provident Institutional Funds
           Account No. [INTENTIONALLY OMITTED]. As of the date hereof,
           immediately after such transfer, the net fair market value of
           Bonfield's assets and liabilities is in excess of $100 million

3.    (a)  The Guaranty is hereby amended to restate Section 9 of the Guaranty
           so that it shall read in its entirety as set forth below:

           9.  The Guarantor's obligations hereunder will terminate, as to
           existing and future indebtedness, upon the earlier of (a) September
           30, 2001 or (b) such day on which each of the guaranteed accounts
           shall have been in compliance (assuming the absence of this guaranty)
           for 20 consecutive trading days with all applicable Legg Mason margin
           requirements (which will not be changed with respect to the
           guaranteed accounts except in connection with changes generally
           applicable to all Legg Mason margin accounts) . In addition, by
           written notice to you effective upon your receipt of such notice, the
           Guarantor may at any time terminate its obligations and your rights
           hereunder in respect of future transactions in the guaranteed
           accounts, but notwithstanding such termination as to future
           transactions the obligations of the Guarantor hereunder with respect
           to any indebtedness in the guaranteed accounts shall continue in full
           force and effect until such indebtedness with interest to the date of
           payment thereon has been paid to you.

      (b)  The Guaranty is hereby amended to include the following language at
           the end of Section 5 of the Guaranty:

          To secure Guarantor's obligations under this Guaranty, the Guarantor
          hereby grants to you a security interest in and lien on up to
          $35,000,000 of all of such moneys, securities or other property, with
          respect to which you shall all the rights and remedies of a secured
          party under the Uniform Commercial Code and under any other applicable
          law, as the same may from time to time be in effect in the State of
          Maryland, in addition to those rights granted herein and in any other
          agreement now or hereafter in effect between the Guarantor and you.
          The Guarantor agrees that upon a default by Guarantor in the
          performance of its obligations hereunder which continue after notice
          by you, you may proceed at any time, in your discretion, to enforce
          this security interest and lien; that the enforcement by you of said
          security interest and lien, in whole or in part, shall not in any way
          affect the continuing liability of the Guarantor hereunder, that any
          demand on the Guarantor to perform the obligations of this Guaranty,
          or any action or proceedings brought to enforce the liability of the
          Guarantor hereunder, shall not release or otherwise affect said
          security interest and lien or right to transfer; and that you shall at
          all times have both the personal liability of the Guarantor and said
          security interest and lien to secure to you the performance of
          Guarantor's obligations hereunder, enforcement of both of which may be
          pursued concurrently.  The Guarantor agrees that you may file such
          financing statements as you may deem necessary to protect your
          security interest in the Guarantor's account or accounts maintained
          with you for the purpose of securing the Guarantor's obligations under
          this Guaranty.

4.    The obligations of the Guarantor under the guaranty shall extend, upon the
      same terms and conditions, to each of Bonfield's affiliates other than
      Safeguard, Safeguard Scientifics (Delaware), Inc. or Safeguard Delaware,
      Inc.

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<PAGE>

5.    This Agreement and its enforcement shall be governed by, and construed in
      accordance with, the laws of the State of Maryland.

6.    (a) Arbitration is final and binding on the parties.

      (b) The parties are waiving the right to seek remedies in court, including
      the right to a jury trial.

      (c) Pre-arbitration discovery is generally more limited than and different
      from court proceedings.

      (d) The arbitrators' award is not required to include factual findings or
      legal reasoning and any party's right to appeal or to seek modification of
      rulings by the arbitrators is strictly limited.

      (e) The panel of arbitrators will typically include a minority of
      arbitrators who were or are affiliated with the securities industry.

      Any controversy between you (together with any of your affiliates also
      involved in such controversy) or any of your or their officers, directors,
      employees or agents on the one hand and the Guarantor or Guarantor's
      officers, directors, employees or agents on the other hand, arising out of
      or relating to this agreement, the transactions contemplated hereby, the
      accounts established hereunder or the guaranteed accounts shall be settled
      by arbitration, in accordance with the rules then obtaining of The New
      York Stock Exchange, Inc., or any other exchange of which you are a
      member, or the National Association of Securities Dealers, Inc. If the
      Guarantor does not make such election by registered mail addressed to you
      at your main office within ten (10) days after receipt of notification
      from you requesting such election, then the Guarantor authorizes you to
      make such election on the Guarantor's behalf. The award of the arbitrator
      shall be final, and judgment upon the award rendered may be entered in any
      court, state or federal, having jurisdiction.

      No person shall bring a putative or certified class action to arbitration,
      nor seek to enforce any pre-dispute arbitration agreement against any
      person who has initiated in court a putative class action or who is a
      member of a putative class who has not opted out of the class with respect
      to any claims encompassed by the putative class action until (i) the class
      certification is denied; (ii) the class is decertified; or (iii) the
      Guarantor is excluded from the class by the court.

      Such forbearance to enforce an agreement to arbitrate shall not constitute
      a waiver of any rights under this agreement except to the extent stated
      herein.

6.    Any notice given by the Guarantor to you under this Guaranty of Account
      shall be effective only when received by the General Counsel of Legg Mason
      Wood Walker, Incorporated, 100 Light Street, Baltimore, MD 21202. Any
      notice given by you to the Guarantor under this Guaranty of Account shall
      be effective only when received by the President of Bonfield Insurance,
      Ltd., c/o the Chief Financial Officer of Safeguard Scientifics, Inc., 435
      Devon Park Drive, Building 800, Wayne, Pennsylvania 19087.

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<PAGE>

      IN WITNESS WHEREOF, the undersigned, intending to be legally bound, have
executed this Assumption of Guaranty Agreement on the date first above written.

                                       SAFEGUARD SCIENTIFICS, INC.

                                       By  /s/ Gerald A. Blitstein
                                           -----------------------

  Witnessed:

  /s/ N. Jeffrey Klauder
  ----------------------

                                       BONFIELD INSURANCE, LTD.

                                       By  /s/ N. Jeffrey Klauder
                                           ----------------------

  Witnessed:

  /s/ Gerald A. Blitstein
  -----------------------

  Accepted and Agreed by Legg Mason Wood Walker, Incorporated

  By /s/ Robert donovan
     ------------------

  Witnessed:

  /s/ Thomas c. Merchant
  ----------------------

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