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                                                                  Exhibit 4.1(b)


            SECOND AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT


         This Second Amended and Restated Registration Rights Agreement (the
"Second Restated Agreement") is made and entered as of this 23rd day of March,
2000 by and among FreeMarkets, Inc., a Delaware corporation (the "Company"), and
the parties listed on Schedule A hereto (the "Existing Security Holders") and
the parties listed on Schedule B hereto (the "New Security Holders" and together
with the Existing Security Holders, the "Security Holders").


                                 R E C I T A L S

         WHEREAS, the Existing Security Holders and the Company are parties to
an Amended and Restated Registration Rights Agreement dated August 3, 1999 (the
"First Restated Agreement");

         WHEREAS, the First Restated Agreement relates to the registration,
under the Securities Act of 1933, as amended, of certain securities owned by the
Existing Security Holders;

         WHEREAS, in connection with the acquisition by the Company of
iMark.com, Inc. ("iMark") pursuant to the Agreement and Plan of Merger dated as
of March 14, 2000 (the "iMark Merger Agreement"), the Company and the Existing
Security Holders desire to further amend and restate the First Restated
Agreement in order, among other things, to add the New Security Holders to the
Second Restated Agreement and to grant certain registration rights to the New
Security Holders on the terms and conditions set forth herein;

         WHEREAS, the Company and the Existing Security Holders have agreed that
this Restated Agreement shall supersede the First Restated Agreement in its
entirety and that the rights and obligations of the parties with respect to the
registration of the Registrable Securities (as defined below) shall be governed
solely by this Second Restated Agreement;

         WHEREAS, the Existing Security Holders who are executing counterpart
signature pages to this Second Restated Agreement have the requisite power and
authority to amend and restate the First Restated Agreement pursuant to the
terms thereof.

         NOW THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the Company and the Security
Holders hereby agree as follows:


         1. Certain Definitions. As used in this Second Restated Agreement, the
following terms shall have the following meanings:


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                  (a) "Business Day" shall mean any day other than a Saturday,
Sunday or a day on which banks in the State of New York are required or
permitted to close.

                  (b) "Common Stock" shall mean the Common Stock, par value
$0.01 per share, of the Company.

                  (c) "Form S-3 Eligibility Date" means the date on which the
Company becomes eligible to file a registration statement on Form S-3 under the
1933 Act.

                  (d) "Holder" means a Security Holder and any assignee of the
rights of such Security Holder in accordance with Section 13(d) of this Second
Restated Agreement.

                  (e) "iMark Merger Shares" means (i) prior to the Form S-3
Eligibility Date, 50% of the shares of Common Stock, other than Lock-Up Shares,
issued to the former stockholders of iMark pursuant to the iMark Merger
Agreement, (ii) following the Form S-3 Eligibility Date, 100% of the shares of
Common Stock, including Lock-Up Shares, issued to the former stockholders of
iMark pursuant to the iMark Merger Agreement, and (iii) in the event of an
underwritten public offering prior to the Form S-3 Eligibility Date, 100% of the
shares of Common Stock, other than Lock-Up Shares, issued to the former
stockholders of iMark pursuant to the iMark Merger Agreement.

                  (f) "Lock-Up Shares" means shares of Common Stock which are
subject to lock-up arrangements entered into by certain former stockholders of
iMark in connection with the acquisition of iMark by the Company pursuant to the
iMark Merger Agreement.

                  (g) "Prospectus" shall mean the prospectus included in any
Registration Statement, as amended or supplemented by any prospectus supplement
with respect to the terms of the offering of any portion of the Registrable
Securities covered by such Registration Statement and by all other amendments
and supplements to the prospectus, including post- effective amendments and all
material incorporated by reference in such prospectus.

                  (h) "Series A Preferred Stock" shall mean the Series A-1
Convertible Preferred Stock, par value $.01 per share, of the Company, and
Series A-2 Convertible Preferred Stock, par value $.01 per shares, of the
Company.

                  (i) "Series B Preferred Stock" shall mean the Series B
Convertible Preferred Stock, par value $.01 per share, of the Company.

                  (j) "Series C Preferred Stock" shall mean the Series C
Convertible Preferred Stock, par value $.01 per share, of the Company.

                  (k) "Series D Preferred Stock" shall mean the Series D
Convertible Preferred Stock, par value $.01 per share, of the Company.


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                  (l) "Register," "registered" and "registration" refer to a
registration effected by preparing and filing a registration statement or
similar document in compliance with the 1933 Act (defined below), and, unless
the context otherwise requires, the declaration or ordering of effectiveness of
such registration statement or document.

                  (m) "Registrable Securities" shall mean (i) Common Stock
acquired upon the conversion of the Series A Preferred Stock, Series B Preferred
Stock, Series C Preferred Stock, Series D Preferred Stock or Warrants, as
defined, (ii) Common Stock owned by American Express Travel Related Services or
Stephen Getsy, (iii) Common Stock owned by Glen T. Meakem and Sam E. Kinney,
Jr., (iv) iMark Merger Shares, and (v) any Common Stock of the Company issued as
(or issuable upon the conversion, exchange or exercise of any warrant, right or
other security which is issued as) a dividend or other distribution with respect
to, or in exchange for or in replacement of, such Common Stock; provided,
however, that "Registrable Securities" shall not include (A) any shares that
have previously been registered or sold to the public; (B) any securities of the
Company which may be sold pursuant to Rule 144 (k) under the 1933 Act or any
successor rule; or (C) Lock-Up Shares; provided, further, the iMark Merger
Shares owned by any former stockholder of iMark shall be deemed "Registrable
Securities" only to the extent that such former stockholder has executed a
counterpart signature page to this Second Restated Agreement.

                  (n) "Registration Statement" shall mean any registration
statement of the Company that covers any of the Registrable Securities pursuant
to the provisions of this Restated Agreement, including the Prospectus,
amendments and supplements to such Registration Statement, including
post-effective amendments, all exhibits and all material incorporated by
reference in such registration statement.

                  (o) "SEC" means the U.S. Securities and Exchange Commission.

                  (p) "1933 Act" means the Securities Act of 1933, as amended,
and the rules and regulations promulgated thereunder.

                  (q) "1934 Act" means the Securities Exchange Act of 1934, as
amended, and the rules and regulations promulgated thereunder.

                  (r) "Warrants" shall mean warrants (i) issued by the Company
to United Technologies Corporation, (ii) Saturn Capital, Inc., and (iii)
Wybrook, L.P.

         2. Piggyback Registrations.

                  (a) Right to Piggyback. Whenever the Company proposes to
register any of its securities under the 1933 Act, other than pursuant to a
registration on Forms S-4 or S-8 (or any successor form or forms), the Company
will give 20 days prior written notice to each Holder of Registrable Securities
of the intention to effect such a registration and, subject to the provisions of
subsection (b) hereof, will include in such registration all Registrable
Securities with respect to which the Holder has given notice of request for
inclusion therein to the Company


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within 15 days after the Company gives such notice (a "Piggyback Registration");
provided that the Company shall have the right to postpone or withdraw any
registration effected pursuant to this Section 2(a) without obligation to any
Holder.

                  (b) Priority on Piggyback Registration. In the event that any
Piggyback Registration is an underwritten public offering, the number of
Registrable Securities to be included in such an underwriting may be reduced
(pro rata among the Holders of Registrable Securities who have requested
registration of Registrable Securities based upon the number of Registrable
Securities requested to be registered by such Holders) if and to the extent that
the managing underwriter shall advise the Company that such inclusion would
adversely affect the marketing of the securities to be sold by the Company
therein, provided, however, that if any shares are to be included in such
underwriting for the account of any person ("Other Security Holder") other than
the Company or Holders of Registrable Securities, such shares of the Other
Security Holder will be reduced to zero before any reduction shall be made in
the number of Registrable Securities to be included in such registration by all
Holders of Registrable Securities.

         3. Demand Registrations. If at any time following the date which is one
hundred eighty (180) days after the initial public offering by the Company, one
or more of the Holders of an aggregate of not less than 20% of the Registrable
Securities ("Initiating Holders") then outstanding shall notify the Company in
writing that it or they intend to offer or cause to be offered for public sale
all or any portion of their Registrable Securities ("Demand Request"), the
Company will notify all other Holders of Registrable Securities (the "Company
Notice"). The Company shall file as soon as practicable, and in any event within
60 days of the receipt of the Demand Request, a registration statement, and use
its best efforts to cause such registration statement to become effective, with
respect to the registration of such Registrable Securities as may be requested
by the Initiating Holders and such other Registrable Securities owned by any
other Holders with respect to which the Company has received written requests
for inclusion within 20 days of the Company Notice. Anything herein to the
contrary notwithstanding, the Company shall be obligated to comply with this
Section 3 on two occasions only. Notwithstanding the foregoing, if the Company
shall furnish to the Initiating Holder(s) a certificate signed by the Chief
Executive Officer of the Company stating that in the good faith judgment of the
Board of Directors of the Company it would be materially detrimental to the
Company and its stockholders for such registration statement to be filed and it
is therefore desirable to defer the filing of such registration statement, the
Company shall have the right to defer taking action with respect to such filing
for a period of 90 days after receipt of the Demand Request.

         4. Registration on Form S-3. At such time as the Company is qualified
to register its securities on Form S-3, and in addition to the rights contained
in Section 2, if at any time a Holder or Holders of Registrable Securities (the
"Initiating Form S-3 Holders") requests that the Company file a registration
statement on Form S-3 for a sale or public offering of all or any portion of the
Registrable Securities held by such Initiating Form S-3 Holder or Holders (the
"Form S-3 Demand"), the reasonably anticipated aggregate price to the public of
which would exceed $5,000,000, then the Company (a) will promptly give at least
20 days written notice of the proposed registration to all other Holders and (b)
use its best efforts to register under the


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Securities Act on Form S-3, for public sale in accordance with the method of
disposition specified in the Form S-3 Notice, the number of Registrable
Securities specified in such Form S- 3 Notice together with any Registrable
Securities requested to be included by any other Holders joining in such request
as are specified in a written request given within 15 days after receipt of such
written notice from the Company. Notwithstanding the foregoing, if the Company
shall furnish to the Initiating Form S-3 Holder(s) a certificate signed by the
Chief Executive Officer of the Company stating that in the good faith judgment
of the Board of Directors of the Company it would be materially detrimental to
the Company and its stockholders for such registration statement to be filed and
it is therefore desirable to defer the filing of such registration statement,
the Company shall have the right to defer taking action with respect to such
filing for a period of 90 days after receipt of the Form S-3 Demand.

         5. Holdback Agreements. Each holder of Registrable Securities agrees
not to effect any public sale or distribution of equity securities of the
Company, or any securities convertible into or exercisable for such securities,
for a period of 180 days beginning on the effective date of any underwritten
registration in which such Holder's Registrable Securities are included (except
as part of such underwritten registration) unless the underwriters managing the
registered public offering otherwise agree; provided, that in no event shall a
holder of Registrable Securities be subject to a limitation on sale or
distribution that covers a period longer than that to which any other security
holder whose securities are included in the registration is subject, and
provided further, that the limitation set forth herein shall not apply to any
securities of the Company which are purchased in a public offering registered
under the 1933 Act or in the open market following an initial public offering by
the Company.

         6. Registration Procedures. Whenever the holders of Registrable
Securities have requested that any Registrable Securities be registered pursuant
to this Restated Agreement, the Company will as expeditiously as reasonably
possible:

                  (a) prepare and file with the SEC a Registration Statement
with respect to such Registrable Securities and use its best efforts to cause
such Registration Statement to become effective and to remain continuously
effective for a period which will terminate when all Registrable Securities
covered by such Registration Statement, as amended from time to time, have been
sold or a period of 180 days, whichever is shorter;

                  (b) prepare and file with the SEC such amendments and
post-effective amendments to the Registration Statement and the Prospectus as
may be necessary to keep the Registration Statement effective for the period
specified in Section 6(a) and to comply with the provisions of the 1933 Act and
the 1934 Act with respect to the distribution of all Registrable Securities;
provided that, at a time reasonably prior to the filing of a Registration
Statement or Prospectus, or any amendments or supplements thereto, the Company
will furnish to counsel for the Holders of Registrable Securities included in
such registration, copies of all documents proposed to be filed, which documents
will be subject to the comments of such counsel;


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                  (c) make available for inspection by a representative of the
Holders of Registrable Securities, any underwriter participating in any
distribution pursuant to such registration, and any attorney, accountant or
other agent retained by such representative or underwriter, all financial and
other records, pertinent corporate documents and properties of the Company, and
cause the Company's officers, directors and employees to supply all information
reasonably requested by any such representative, underwriter, attorney,
accountant or agent in connection with such registration statement;

                  (d) notify the counsel for the Holders of Registrable
Securities included in such registration promptly, and, if requested, confirm
such advice in writing, (i) when the Prospectus or any supplement or
post-effective amendment has been filed, and with respect to the Registration
Statement or any post-effective amendment, when the same has become effective,
(ii) of any request by the SEC for amendments or supplements to the Registration
Statement or the Prospectus or for additional information, (iii) of the issuance
by the SEC of any stop order suspending the effectiveness of the Registration
Statement or the initiation of any proceedings for that purpose, and (iv) of the
receipt by the Company of any notification with respect to the suspension of the
qualification of the Registrable Securities for sale in any jurisdiction or the
initiation or threatening of any proceeding for such purpose;

                  (e) make reasonable effort to obtain the withdrawal of any
order suspending the effectiveness of the Registration Statement;

                  (f) deliver to each Holder of Registrable Securities included
in such registration, as the case may be, as many copies of the Registration
Statement and Prospectus (including each preliminary prospectus) and any
amendment or supplement thereto as such holder may reasonably request;

                  (g) prior to any public offering of Registrable Securities,
use its best efforts to register or qualify or cooperate with the holders of
Registrable Securities and the underwriters, if any, and their respective
counsel in connection with the registration or qualification of such Registrable
Securities for offer and sale under the securities or blue sky laws of such
jurisdictions as such Holder or any underwriter reasonably requests in writing,
and do any and all other acts or things necessary or advisable to enable the
distribution in such jurisdictions of the Registrable Securities covered by the
Registration Statement; provided that the Company will not be required to
qualify generally to do business in any jurisdiction where it is not then so
qualified or to take any action which would subject it to general service of
process in any such jurisdiction where it is not then so subject;

                  (h) cause all Registrable Securities covered by the
Registration Statement to be listed on each securities exchange, interdealer
quotation system or other market on which similar securities issued by the
Company are then listed; and provide a transfer agent and registrar for all
Registrable Securities included in such Registration Statement and a CUSIP
number for all such Registrable Securities, in each case not later than the
effective date of such registration;


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                  (i) in the event of any underwritten public offering, enter
into and perform its obligations under an underwriting agreement, usual and
customary in form, with the managing underwriter of such offering (the Holders
of Registrable Securities included in such registration, shall also enter into
and perform their obligations under such agreement, usual and customary in
form); and the Company shall take such other actions as the underwriters
reasonably request in order to expedite or facilitate a disposition of the
Registrable Securities;

                  (j) upon request, furnish to each Holder of Registrable
Securities included in such registration, a signed counterpart, addressed to
such Holder, of (i) an opinion of counsel for the Company, dated the effective
date of such Registration Statement (or, if such registration includes an
underwritten public offering, dated the date of the closing under the
underwriting agreement), and (ii) if permitted, a "comfort" letter, dated the
effective date of such Registration Statement (and, if such registration
includes an underwritten public offering, dated the date of the closing under
the underwriting agreement), signed by the independent public accountants who
have certified the Company's financial statements included in such Registration
Statement;

                  (k) immediately notify each Holder of Registrable Securities
included in such registration, at any time when a Prospectus relating thereto is
required to be delivered under the Securities Act, upon discovery that, or upon
the happening of any event as a result of which, the Prospectus included in such
Registration Statement, as then in effect, includes an untrue statement of a
material fact or omits to state any material fact required to be stated therein
or necessary to make the statements therein not misleading in the light of the
circumstances then existing, and at the request of any such Holder, promptly
prepare and furnish to such Holder a reasonable number of copies of a supplement
to or an amendment of such Prospectus as may be necessary so that, as thereafter
delivered to the purchasers of such Registrable Securities, such Prospectus
shall not include an untrue statement of a material fact or omit to state a
material fact required to be stated therein or necessary to make the statements
therein not misleading in the light of the circumstances then existing;

                  (l) otherwise use its reasonable efforts to comply with all
applicable rules and regulations of the SEC under the 1933 Act and the 1934 Act,
and take such other actions as may be reasonably necessary to facilitate the
registration or the disposition of the Registrable Securities hereunder;

                  (m) In connection with each registration hereunder, the
Holders of Registrable Securities to be included in the registration will
furnish to the Company in writing such information with respect to themselves
and the proposed distribution by them as reasonably shall be necessary in order
to assure compliance with federal and applicable state securities laws. In
addition, the Holders of Registrable Securities agree that they will not deliver
any form of Prospectus in connection with the sale of any Registrable Securities
as to which the Company has advised such Holders that it is preparing an
amendment or supplement.

         7. Expenses. The Company will pay all expenses in connection with any
registration pursuant to Sections 2, 3 and 4, including, without limitation, all
registration and filing fees, printing expenses, fees and disbursements of
counsel and independent public accountants for the


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Company, fees and expenses (including counsel fees) incurred in connection with
complying with state securities or "blue sky" laws, fees of the National
Association of Securities Dealers, Inc., transfer taxes, fees of transfer agents
and registrars, costs of insurance and fees and disbursements of one counsel for
the Holders of Registrable Securities. All underwriting discounts and selling
commissions applicable to the sale of a holder's Registrable Securities will be
paid by such holder.

         8. Indemnification.

                  (a) Indemnification by Company. In connection with any
registration pursuant to this Restated Agreement, the Company agrees to
indemnify and hold harmless, to the fullest extent permitted by law, each Holder
of Registrable Securities included in a registration pursuant to this Restated
Agreement, such Holder's officers, directors, partners and employees and each
person who controls such holder (within the meaning of the 1933 Act) and each
underwriter, if any (including any broker or dealer which may be deemed an
underwriter) and each person who controls any underwriter of the Registrable
Securities against all losses, claims, damages, liabilities, and expenses caused
by (i) any untrue or alleged untrue statement of a material fact contained in
any Registration Statement, Prospectus or any preliminary prospectus or any
amendment or supplement thereto or any omission or alleged omission to state
therein a material fact required to be stated therein or necessary to make the
statements therein not misleading, or (ii) any violation by the Company of any
federal, state or common law, rule or regulation applicable to the Company in
connection with any Registration Statement, Prospectus or any preliminary
prospectus, or any amendment or supplement thereto, and shall reimburse, as
incurred, each of the foregoing persons for any legal and any other expenses
reasonably incurred in connection with investigating or defending any such
claims; provided, however that the indemnity agreement contained in this Section
8(a) shall not apply to amounts paid in settlement of any such loss, claim,
damage, liability, or action if such settlement is effected without the consent
of the Company (which consent shall not unreasonably be withheld), nor shall the
Company be liable to the extent any loss, claim, damage, liability or action
arises out of or is based upon any information furnished in writing to the
Company by any Holder, underwriter or controlling person expressly for use in
connection with such registration.

                  (b) Indemnification by Holder of Registrable Securities. In
connection with any registration pursuant to the terms of this Restated
Agreement, each Holder of Registrable Securities included in such registration
agrees to indemnify and hold harmless, to the fullest extent permitted by law,
the Company, its directors and officers and each person who controls the Company
(within the meaning of the 1933 Act) against any losses, claims, damages,
liabilities and expense resulting from any untrue statement of a material fact
or any omission of a material fact required to be stated in the Registration
Statement or Prospectus or preliminary prospectus or any amendment or supplement
thereto, or necessary to make the statements therein not misleading, to the
extent, but only to the extent, that such untrue statement or omission is
contained in any information furnished in writing by the Holder of Registrable
Securities to the Company specifically for inclusion in such Registration
Statement or Prospectus and that such information was substantially relied upon
by the Company in preparation of the Registration Statement or Prospectus or any
amendment or supplement thereto. In no event shall the liability


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of the Holder of Registrable Securities hereunder be greater in amount than the
lesser of (i) an amount equal to the proportion that the public offering price
of the Registrable Securities sold by the holder in such registration bears to
the total public offering price of all securities sold thereunder or (ii) the
dollar amount of the proceeds (net of all expense paid by such Holder and the
amount of any damages such Holder has otherwise been required to pay by reason
of such untrue statement or omission) received by such Holder upon the sale of
the Registrable Securities pursuant to such registration; provided, however that
the indemnity agreement contained in this Section 8(b) shall not apply to
amounts paid in settlement of any such loss, claim, damage, liability, or action
if such settlement is effected without the consent of the Holder (which consent
shall not unreasonably be withheld).

                  (c) Contribution. If for any reason the indemnification
provided for in the preceding clauses (a) and (b) is judicially determined (by
the entry of a final judgment or decree by a court of competent jurisdiction and
the expiration of time to appeal or the denial of the last right of appeal) to
be unavailable to an indemnified party or insufficient to hold it harmless,
notwithstanding the fact that this Section 8 provides for indemnification in
such case, then the indemnifying party shall contribute to the amount paid or
payable by the indemnified party as a result of such loss, claim, damage or
liability in such proportion as is appropriate to reflect the relative fault of
the indemnified party and the indemnifying party, as well as any other relevant
equitable considerations. The relative fault of the indemnifying party and of
the indemnified party shall be determined by reference to, among other things,
whether the untrue or alleged untrue statement of a material fact or the
omission to state a material fact relates to information supplied by the
indemnifying party or by the indemnified party and the parties' relative intent,
knowledge, access to information, and opportunity to correct or prevent such
statement or omission.

                  (d) Survival of Obligations. The obligations of the parties
under this Section 8 shall survive the completion of the offering of Registrable
Securities and shall remain in full force and effect regardless of any
investigation made by or on behalf of any indemnified party.

         9. Limitations on Subsequent Registration Rights. From and after the
date of this Restated Agreement, the Company shall not, without the prior
written consent of Holder(s) of 66-2/3% (the "Minimum Percentage") of all
Registrable Securities then held by all Holders, enter into any agreement with
any holder or prospective holder of any securities of the Company giving such
holder or prospective holder any registration rights the terms of which are more
favorable than the registration rights granted to the Holders hereunder;
provided, however, for purposes of calculating the Minimum Percentage, there
shall be excluded from the definition of Registrable Securities all iMark Merger
Shares and all Lock-Up Shares, and the iMark Merger Shares and Lock-Up Shares
shall not be voted for any purpose under this Section 9.

         10. Changes in Common Stock. If, and as often as, there is any change
in the Common Stock by way of a stock split, stock dividend, combination or
reclassification, or through a merger, consolidation, reorganization or
recapitalization, or by any other means, appropriate adjustment shall be made in
the provisions hereof so that the rights and privileges granted hereby shall
continue with respect to the Common Stock as so changed.


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         11. Rule 144 Reporting. With a view to making available the benefits of
certain rules and regulations of the Commission that may permit the sale of the
Registrable Securities to the public without registration, the Company agrees
to:

                  (a) make and keep public information available, as those terms
are understood and defined under the 1933 Act, at all times from and after 90
days following the earlier of the effective date of the Company's first
registration under the 1933 Act or the registration of any class of the
Company's securities under Section 12 of the 1934 Act.

                  (b) use its best efforts to file with the Commission in a
timely manner all reports and other documents required of the Company under the
Securities Act and the Exchange Act; and

                  (c) furnish to each Holder of Registrable Securities forthwith
upon request (i) a written statement by the Company as to its compliance with
the reporting requirements of Rule 144 and of the 1933 Act and the 1934 Act,
(ii) a copy of the most recent annual or quarterly report of the Company, and
(iii) such other reports and documents so filed by the Company as such Holder
may reasonable request in availing itself of any rule or regulation of the
Commission allowing such holder to sell any Registrable Securities without
registration.

         12. Amendment and Restatement of First Restated Agreement.

                  (a) The First Restated Agreement amended and restated the
following agreements (collectively, the "Predecessor Agreements") in all
respects: (i) Article 4 of the Shareholders' Agreement dated July 31, 1995
between the Company and Glen T. Meakem and Sam E. Kinney, as amended, pursuant
to authority granted in Section 5.9 thereof; (ii) Section 7.2.5 of the Purchase
Agreement dated August 17, 1995 between the Company and American Express Travel
Related Services Company, Inc. (as clarified by side letter dated April 7,
1999), pursuant to authority granted in Section 10.3 thereof; (iii) Section 10
of the Stock Subscription Agreement dated September 7, 1995 between the Company
and Stephen Getsy, pursuant to authority granted in Section 8 thereof; (iv)
Registration Rights Agreement dated March 29, 1996 between the Company and the
purchasers of Series A-1 Preferred Stock, as amended to date, pursuant to
authority granted in Section 14(b) thereof; (v) Registration Rights Agreement
dated December 29, 1996 between the Company and the purchasers of Series B
Preferred Stock, as amended to date, pursuant to authority granted in Section
14(b) thereof; and (vi) Registration Rights Agreement dated December 2, 1997
between the Company and the purchasers of Series A-2 Preferred Stock, as amended
to date, pursuant to authority granted in Section 14(b) thereof. The parties
acknowledge that no Security Holder shall have any rights under the Predecessor
Agreements.


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                  (b) This Second Restated Agreement amends and restates the
First Restated Agreement in all respects. The Existing Security Holders
executing a counterpart signature page to this Second Restated Agreement have
the requisite power and authority to amend and restate the First Restated
Agreement pursuant to authority granted in Section 13(b) thereof. Each other
Existing Security Holder is bound by the amendment and restatement of the First
Restated Agreement and the terms of this Second Restated Agreement.

         13. Miscellaneous.

                  (a) Remedies. If the Company shall breach its obligations to
register the Registrable Securities pursuant to this Restated Agreement, the
Holders shall be entitled to exercise all rights provided herein or granted by
law, including recovery of damages, or in equity, including specific
performance.

                  (b) Amendments and Waivers. This Restated Agreement may be
amended and the Company may take any action herein prohibited, or omit to
perform any act herein required to be performed by it, only if the Company shall
have obtained the written consent to such amendment, action or omission to act,
of the Holder or Holders of at least 66-2/3% of the Registrable Securities then
held by all Holders (the "Amendment Percentage"); provided, however, for
purposes of calculating the Amendment Percentage, there shall be excluded from
the definition of Registrable Securities all iMark Merger Shares and all Lock-Up
Shares, and the iMark Merger Shares and Lock-Up Shares shall not be voted for
any amendment, action or omission to act for any purpose under this Section
13(b). Notwithstanding the foregoing, except upon the consent in writing of a
majority-in-interest of iMark Merger Shares and Lock-Up Shares, no amendment or
waiver shall be binding on any holder of iMark Merger Shares or Lock-Up Shares,
if such amendment or waiver would materially adversely affect the rights of such
holders as holders of Registrable Securities; provided, however, the granting of
registration rights on a parity with the iMark Merger Shares shall not be deemed
to affect the rights of holders of iMark Merger Shares and Lock-Up Shares
materially and adversely. Each Holder of any Registrable Securities at the time
and any subsequent Holder of Registrable Securities shall be bound by any
consent authorized by this subsection 13(b), whether or not such Registrable
Securities shall have been marked to indicate such consent.

                  (c) Notices. All notices and other communications provided for
or permitted hereunder shall be in writing and shall be deemed to have been duly
delivered (a) when delivered by hand, if personally delivered, (b) if sent by
mail to a party whose address is in the same country as the sender, two Business
Days after being deposited in the mail, postage prepaid, (c) when delivered by
courier as evidenced by receipt from the courier, if delivered by courier, or
(d) if sent by facsimile transmission on a Business Day, upon confirmation of
receipt; provided, however, that if the Company is required to give notice, or
to furnish information or prospectus(es) to holders of iMark Merger Shares
pursuant to the terms of this Second Restated


                                       11

<PAGE>   12



Agreement, the Company may, at its option, elect to satisfy any such requirement
by giving notice, or furnishing such information or prospectus(es) to the
Representative (as defined in the iMark Merger Agreement). All notices provided
by the Company hereunder shall be given to the Security Holders at their
respective addresses appearing in the books and records of the Company.

                  (d) Assignments and Transfers. Each Holder of Registrable
Securities may make an assignment or transfer to any transferee or assignee of
any Registrable Securities, provided, that (i) such transfer is made expressly
subject to this Restated Agreement and the transferee agrees in writing to be
bound by the terms and conditions hereof, and (ii) the Company is provided with
reasonably prompt written notice of such assignment.

                  (e) Benefits of the Agreement. The terms and conditions of
this Restated Agreement shall inure to the benefit of and be binding upon the
respective permitted successors and assigns of the parties.

                  (f) Severability. If one or more provisions of this Restated
Agreement are held to be unenforceable under applicable law, such provision
shall be excluded from this Restated Agreement and the balance of this Restated
Agreement shall be interpreted as if such provision were so excluded and shall
be enforceable in accordance with its terms.

                  (g) Entire Agreement. This Second Restated Agreement is
intended by the parties as a final expression of their agreement and intended to
be a complete and exclusive statement of the agreement and understanding of the
parties hereto in respect of the subject matter contained herein. This Second
Restated Agreement supersedes all prior agreements and understandings between
the parties with respect to such subject matter.

                  (h) Applicable Law. This Restated Agreement shall be governed
by, and construed in accordance with, the laws of the State of Delaware without
regard to principles of conflicts of law.



                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]


                                       12

<PAGE>   13



                  IN WITNESS WHEREOF, the parties have executed this Restated
Agreement as of the date first written above.


                                             FREEMARKETS, INC.


                                             By: /s/ GLEN T. MEAKEM
                                                ------------------------------
                                                     Glen T. Meakem
                                                     President




                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]



<PAGE>   14



                  SIGNATURE PAGE TO SECOND AMENDED AND RESTATED
                          REGISTRATION RIGHTS AGREEMENT



                                         SECURITY HOLDER



                                         ------------------------------
                                         Printed Name


                                         ------------------------------
                                         Signature


                                         ------------------------------
                                         Date





<PAGE>   15



Additional Signature Pages of the Following Parties Omitted

Goldman Sachs Group, Inc.
Stone Street Fund 1999, L.P.
Nevada Bond Investment Corp. II
Saturn Capital, Inc.
Glen T. Meakem
Sam E. Kinney, Jr.
Nelia Araujo
Austin Ventures VI Affiliates Fund, L.P.
Austin Ventures VI, L.P.
Ricardo Castaneda
Robert Chiste
Comdisco
CNA Trust Corporation TTEE for The Venture Law Group
401(k) Retirement Savings Plan FBO: Mitchell S. Zuklie
CNA Trust Corporation TTEE for Venture Law Group
401(k) FBO Glen R. Van Ligten
J. Ross Cockrell
Curly H Ventures, LTD.
Michael Dickson
Sophia Dilberakis
Bosko Durickovic
Fariseu Investmentos E Servicos, LDA.
Issam Faza
Sharon Hendricks
Douglas G. Hibberd
Gregory J. Ikonen
Impact Venture Partners
Paul Jendrzey
Steven Kaplan
Donald M. Keller, Jr.
Robert E. Kornblum
Kirk Lockhart
Brian Magierski
Richard Merritt
Dave Milam
Elizabeth Moline
Paul Ohls
Scott Patterson
Glenn Rau
Robert Sanchez
Mark Saul
Marc Schriftman
Techxas Fund v 1.0, L.P.
Jeff Thomas
VLG Investments 1999
Rob Volkel
Mel Williams
Mark Winfeld Hansen
Mitchel Zuklie


<PAGE>   16


                                   SCHEDULE A
                            EXISTING SECURITY HOLDERS

American Express Travel Related Services Co.
ATGF II
Raymond C. and Mary Jo Becker
Birchmere Investments
Francis M. Bricmont
Barry B. and Sheila A. Bridger
Ralph H. Cechettini 1995 Trust
Ralph H. Cechettini IRA Rollover
Daniel F. Chapey
Anthony Ciulla
CSM Partners
Robert B. and Ann M. Eagan
James M. Edwards
Jack W. Elliott
Matthew O. Fitzmaurice
Stephen J. Getsy
Goldman Sachs Group, Inc.
Sam E. Kinney, Jr.
Keith B. and Jane M. Kirkland
Robert Kopf
Thomas Kopf
John P. Levis, III
Christopher Lord
Glen T. Meakem
Douglas T. and Deborah L. Millar
Nevada Bond Investment Corp. II
Hugh W. Nevin, Jr.
David A. Noble
Pivotal Application Fund
Pivotal Partners, LP
Saturn Capital, Inc.
Sean Sebastian
William S. Slattery
James Stableford
Stone Street Fund 1999, L.P.
Vertex Capital II, LLC
Marc Weiss


<PAGE>   17


                                   SCHEDULE B
                              NEW SECURITY HOLDERS


Nelia Araujo
Ricardo Castaneda
Michael Dickson
Bosko Durickovic
Douglas G. Hibberd
Paul Jendrzey
Gregory J. Ikonen
Donald M. Keller, Jr.
Robert E. Kornblum
Kirk Lockhart
Brian Magierski
Richard Merritt
Dave Milam
Elizabeth Moline
Paul Ohls
Scott Patterson
Glenn Rau
Robert Sanchez
Marc Schriftman
Rob Volkel
Mel Williams
Austin Ventures VI Affiliates Fund, L.P.
Austin Ventures VI, L.P.
Robert Chiste
Comdisco
CNA Trust Corporation TTEE for The Venture Law Group
401(k) Retirement Savings Plan FBO: Mitchell S. Zuklie
CNA Trust Corporation TTEE for Venture Law Group
401(k) FBO Glen R. Van Ligten
J. Ross Cockrell
Curly H Ventures, LTD.
Sophia Dilberakis
Fariseu Investmentos E Servicos, LDA.
Issam Faza
Sharon Hendricks
Steven Kaplan
Donald M. Keller, Jr.
Robert E. Kornblum
Glenn Rau
Robert Sanchez
Mark Saul
Techxas Fund v1.0, L.P.
Glen R. Van Ligten
VLG Investments 1999
Mark Windfeld-Handsen
Mitchell S. Zuklie
Impact Venture Partners