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                                                                     Exhibit 4.7

                     PIGGYBACK REGISTRATION RIGHTS AGREEMENT


          This Piggyback Registration Rights Agreement dated as of January 27,
2000 (this "Agreement") is entered into by and among Interliant, Inc., a
Delaware corporation (the "Company"), and each Person signatory hereto and each
Person that becomes signatory hereto after the date hereof as contemplated
hereby (each a "Stockholder" and together the "Stockholders").

                              W I T N E S S E T H :

          WHEREAS, during the first quarter of 2000, the Company at one or more
closings is selling Equity Securities to certain Persons pursuant to certain
Securities Purchase Agreements between the Company and such Persons (the Persons
acquiring Equity Securities from the Company during the first quarter of 2000
are hereafter referred to as the "First Quarter 2000 Persons") and it is a
condition to the consummation of the transactions contemplated by those
agreements that the Company grant such First Quarter 2000 Persons certain
piggyback registration rights as contemplated by this Agreement;

          WHEREAS, the Company has previously granted piggyback registration
rights to the Prior Piggyback Persons (as defined herein) pursuant to (1) that
certain Investors Agreement, dated as of January 28, 1999, (2) that certain
Registration Rights Agreement, dated as of December 8, 1997, (3) that certain
Shareholders Agreement, dated as of March 10, 1999, (4) that certain Agreement
and Plan of Merger (relating to Triumph Technologies, Inc.), dated November 12,
1999, (5) that certain Agreement and Plan of Merger (relating to Triumph
Development, Inc.) dated November 12, 1999 and (6) that certain Agreement and
Plan of Merger (relating to The Jacobson Group, Inc.) dated December 21, 1999;

          WHEREAS, the parties hereto contemplate that after the date hereof,
some or all of the Prior Piggyback Persons shall become party to this Agreement
and shall become a Stockholder and Holder hereunder;


          NOW, THEREFORE, in consideration of the mutual promises, agreements
and covenants set forth herein, and for other good and valuable consideration,
the receipt and sufficiency of which are hereby acknowledged, the parties
hereto, intending legally to be bound, hereby agree as follows:

                                   Article I.

                                   DEFINITIONS

          Section  1.01 Defined  Terms.  The  following  terms when used in this
Agreement,  including its preamble and recitals, shall, except where the context
otherwise
<PAGE>

requires, have the following meanings, such meanings to be equally applicable to
the singular and plural forms thereof:

                  "Affiliate" shall mean, with respect to any Person, any person
that, directly or indirectly, controls, is controlled by or is under common
control with such Person. For the purposes of this definition, "control"
(including, with correlative meanings, the terms "controlled by" and "under
common control with"), as used with respect to any Person, shall mean the
possession, directly or indirectly, of the power to direct or cause the
direction of the management and policies of such Person, whether through the
ownership of voting securities or by contract or otherwise.

                  "Common Stock" shall mean the common stock, par value $0.01
per share, of the Company.

                  "Equity Securities" shall mean any Common Stock, any
securities exercisable or exchangeable for or convertible into Common Stock and
any rights, options or warrants to acquire any of the foregoing.

                  "First Quarter 2000 Persons" shall mean those Stockholders
described in the recitals hereto.

                  "Holders" shall mean (1) the First Quarter 2000 Persons; (2)
any of the Prior Piggyback Persons who agree to become party to this Agreement;
and (3) New Purchasers, provided, however, that the First Quarter 2000 Persons
shall only be Holders hereunder on or after January 27, 2001.

                  "Jacobson  Persons" shall mean Patricia K. Jacobson,  Barry H.
Jacobson,  Richard  W.  Weissberg,  Michael S.  Kirschenbaum  and  Elizabeth  W.
Reiland.

                  "New Purchasers" shall mean Persons who acquire Equity
Securities of the Company in connection with an acquisition by the Company
following the date of this Agreement and who are granted piggyback rights which
are pari passu with the piggyback rights granted to the Holders hereunder.

                  "Non-Party Prior Piggyback Persons" shall mean such Prior
Piggyback Persons who do not become party to this Agreement.

                  "Person" shall mean and include an individual, a corporation,
a limited liability company, an association, a partnership, a joint venture, a
trust or estate, a government or any department or agency thereof, or any other
entity or governmental body.

                  "Prior Piggyback Person" shall mean any member (and "Prior
Piggyback Persons" shall mean all members) of the following groups: (1) the Wolf
Persons, (2) WHO, (3) the Softbank Persons, (4) the Triumph Persons and (5) the
Jacobson Persons.

                  "Registration Expenses" shall mean all expenses incident to
the Company's performance of or compliance with its obligations under Sections
2.01 and 2.04 hereof, including without limitation, all SEC, NASD and stock
exchange or NASDAQ registration and filing fees

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<PAGE>

and expenses, fees and expenses of compliance with applicable state securities
or "blue sky" laws (including, without limitation, reasonable fees and
disbursements of counsel for the underwriters in connection with "blue sky"
qualifications of securities registered in accordance with this Agreement),
printing expenses, messenger and delivery expenses, the fees and expenses
incurred in connection with the listing of the securities to be registered on
each securities exchange or national market system on which such securities are
listed, fees and disbursements of counsel for the Company and all independent
certified public accountants retained by the Company (including the expenses of
any annual audit and "cold comfort" letters required by or incident to such
performance and compliance), all reasonable fees and expenses of one counsel to
the Holders participating in a Piggyback Registration, the fees and
disbursements of underwriters customarily paid by issuers or sellers of
securities (including the fees and expenses of any "qualified independent
underwriter" required by the NASD), the reasonable fees and expenses of any
special experts retained by the Company in connection with such registration,
fees and expenses of other Persons retained by the Company in connection with
such registration, all transfer taxes with respect to the shares of Common Stock
sold by a Stockholder and all other expenses incurred by Stockholders customary
for and incidental to the sale and delivery of the shares of Common Stock to be
sold by such Stockholders (but not including any underwriting discounts or
commission, if any, attributable to the sale of Common Stock by holders of such
Common Stock other than the Company).

                  "SEC" shall mean the Securities and Exchange Commission.

                  "Securities Act" shall mean the Securities Act of 1933, as
amended.

                  "Softbank  Persons" shall mean Softbank  Technologies  Venture
IV, L.P. and Softbank Technologies Advisors Fund, L.P.

                  "Triumph Persons" shall mean Steven R. Munroe, Brad D. Munroe,
Peter Hawtrey and Robert F. Munroe.

                  "WHO" shall mean WEB Hosting  Organization  L.L.C., a Delaware
limited liability company.

                  "Wolf  Persons" shall mean Mathew Wolf, Ann Weltchek Wolf 1995
Marital Trust,  Mathew D. Wolf  Children's  Trust,  Michael August and Broadview
Holdings LLP.

                                   Article II.

                               REGISTRATION RIGHTS

                  Section 2.01 Piggyback Registration. (a) If the Company
proposes (including in connection with any demand registration which a Person
may have) to file any registration statement under the Securities Act with
respect to any Common Stock (other than pursuant to a registration statement on
Form S-4 or S-8 or any successor or similar forms in connection with an exchange
offer or any offering of securities solely to the Company's then existing
stockholders or employees of the Company and its subsidiaries), the Company
shall give written notice of such proposed filing to the Holders at least 30
days prior to such proposed filing. Such notice shall offer to the Holders the
opportunity to include in such registration statement for

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resale by the Holders, such number of shares of Common Stock each may request in
a written notice to the Company (which notice shall specify the number of shares
to be disposed of by such Holder and the intended method of disposition thereof)
within 20 days after the receipt of such notice from the Company (a "Piggyback
Registration"). The Company shall permit, or shall cause the managing
underwriter of any such proposed offering to permit, the shares of Common Stock
requested to be included in the registration to be included on the same terms
and conditions as are applicable to the other shares of Common Stock included in
such registration statement, subject to Section 2.01(b) below. The Company shall
not be required to maintain the effectiveness of the registration statement
beyond the earlier to occur of (i) 180 days after the effective date of the
registration statement; and (ii) consummation of the distribution by the Holders
of the shares of Common Stock that are included in such registration statement.

                  (b) If the managing underwriter or underwriters, if any,
advise the Holders in writing that in its or their opinion, the number of shares
of Common Stock proposed to be sold in such registration (including shares of
Common Stock to be included pursuant to Section 2.01(a) above) will materially
adversely affect the success of such offering, the Company will include in such
registration the number of shares of Common Stock, if any, which in the opinion
of such underwriter or underwriters, or the Company, as the case may be, can be
sold as follows: (i) first, the shares the Company proposes to sell (or, in the
case of a demand registration, the shares of Common Stock the Person(s)
initiating such demand registration proposes to sell); and (ii) second, the
shares of Common Stock requested to be included in such registration by the
Holders and the Non-Party Prior Piggyback Persons; provided that (a) if all the
shares of Common Stock requested to be included in such Piggyback Registration
set forth above are not to be included, selection of shares of Common Stock to
be included shall be made pro rata based on the number of shares of Common Stock
that such Holder and the Non-Party Prior Piggyback Persons hold and (b) none of
the Holders shall have the right to register shares pursuant to this Section
2.01 if the Company is at such time, and has been continuously during the
immediately preceding three years, subject to the reporting requirements of
Section 13 or 15(d) of the Exchange Act and such Holder is then entitled to sell
all of its shares of Common Stock without any volume restrictions pursuant to
Rule 144 of the Securities Act or all of such shares of Common Stock may be sold
pursuant to Rule 144(k) of the Securities Act.

                  Section 2.02 Holdback Agreement. Notwithstanding any other
provision in this Article 2, the Company and the Stockholders each agree that it
will not, and the Company shall use its best efforts to not permit any Affiliate
to (and it shall be a condition to the rights of each Stockholder under this
Article 2 that such Stockholder does not) offer for public sale any shares of
Equity Securities, or effect any sale of securities pursuant to Rule 144, during
the 10 days prior to and the 180 days after the closing date of any underwritten
offering of Equity Securities unless such shares are covered by such
registration statement or such shorter period is agreed to by any managing
underwriter or underwriters of such offering.

                  Section 2.03 Expenses. All Registration Expenses,
disbursements and fees incurred by the Company and the Holders in connection
with any registration under this Article 2 shall be borne by the Company.

                  Section 2.04 Registration  Procedures.  In connection with the
registration of shares of Common Stock under the Securities Act pursuant to this
Agreement,  the  Company,  will

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<PAGE>

furnish each Holder whose shares of Common Stock are registered thereunder and
each underwriter, if any, with a copy of the registration statement (including
all exhibits thereto) and all amendments thereto and will supply each such
Holder and each underwriter, if any, with copies of any prospectus included
therein (including a preliminary prospectus and all amendments and supplements
thereto) in such quantities as may be reasonably necessary for the purposes of
the proposed sale or distribution covered by such registration.

                  Notwithstanding anything to the contrary herein, the only
securities which the Company shall be required to register subject to and
pursuant to this Article 2 shall be shares of Common Stock; provided, however,
that in any underwritten public offering, the Holders of any outstanding Equity
Securities shall be entitled to sell such Equity Securities to the underwriters
for exercise, exchange or conversion and sale of the shares of Common Stock
issued upon exercise, exchange or conversion thereof.

                  It is hereby agreed that the Holders shall have piggyback
registration rights, as described in this Article 2, only with respect to the
Equity Securities that such Person initially acquired from the Company,
provided, however, that to the extent that any of the Triumph Persons and/or the
Jacobson Persons become Holders hereunder, such Person shall have piggyback
registration rights with respect to any earnout shares that such Person may
receive from the Company pursuant to the terms of the merger agreement to which
such Persons, on the one hand, and the Company, on the other hand, are parties.

                  In connection with the Company's registration obligations
pursuant to this Article 2, the Company will use its best efforts to effect such
registration to permit the sale of such shares of Common Stock in accordance
with the intended method or methods of disposition thereof, and pursuant thereto
the Company will:

                  (a) prepare and file with the SEC, as soon as practicable
after receiving a written notice pursuant to Section 2.01, a registration
statement on any appropriate form under the Securities Act, which form shall be
selected by the Company (and shall be reasonably acceptable to any managing
underwriter chosen by holders of shares covered by such registration statement)
and shall be available for the sale of the shares in accordance with the
intended method or methods of distribution thereof, and use its reasonable
efforts to cause such registration statement to become effective; provided that
before filing a registration statement or any prospectus related thereto or any
amendments or supplements thereto, including documents incorporated by reference
after the initial filing of any registration statement, the Company will furnish
copies of all such documents proposed to be filed to the holders of the shares
covered by such registration statement and underwriters, if any, and make the
Company's representatives available for discussion of such documents and other
relevant matters and shall reasonably consider such changes in such documents
prior to the filing thereof as such holders or underwriters may timely and
reasonably request. If any Holder whose shares of Common Stock are covered by
such registration statement shall reasonably object to any disclosure in or
omission from any registration statement or any amendment thereto or any
prospectus or any supplement thereto (including documents incorporated by
reference) which the Company in good faith on the advice of counsel believes is
necessary or appropriate to be included therein or omitted therefrom, and prior
to the effectiveness of such registration advises the Company that it

                                       5
<PAGE>

chooses  not to  participate  in such  offering,  such  Holder may choose not to
participate in such offering;

                  (b) prepare and file with the SEC such amendments and
post-effective amendments to the registration statement as may be necessary to
keep such registration statement effective for the required duration thereof;
cause the related prospectus to be supplemented by any required prospectus
supplement, and as so supplemented to be filed pursuant to Rule 424 under the
Securities Act; and comply with the relevant provisions of the Securities Act
during the applicable period in accordance with the intended methods of
disposition by the sellers thereof set forth in such registration statement or
supplement to such prospectus;

                  (c) notify the selling Holders and the managing underwriters,
if any, promptly, and (if requested by any such holders) confirm such advice in
writing, (A) when a prospectus or any prospectus supplement or post-effective
amendment has been filed, and, with respect to a registration statement or any
post-effective amendment, when the same has become effective, (B) of any request
by the SEC for amendments or supplements to a registration statement or related
prospectus or for additional information, (C) of the issuance by the SEC of any
stop order suspending the effectiveness of a registration statement or the
initiation of any proceedings for that purpose, (D) of the receipt by the
Company of any written notification with respect to the suspension of the
qualification of any of the shares for sale in any jurisdiction or the
initiation or threatening of any proceeding for such purpose, and (E) of the
existence of any fact known to the Company which results in a registration
statement, a prospectus or any document incorporated therein by reference
containing an untrue statement of a material fact or omitting to state a
material fact necessary to make the statements therein, in light of the
circumstances under which they were made, not misleading;

                  (d) use  reasonable  efforts to obtain the  withdrawal  of any
order suspending the  effectiveness of a registration  statement at the earliest
practicable moment;

                  (e) if reasonably requested by the managing underwriters or a
selling Holder, promptly incorporate in a prospectus supplement or
post-effective amendment such information as the managing underwriters or a
selling Holder agree should be included therein, subject to the last sentence of
Section 2.04(a); and promptly make all required filings of such prospectus
supplement or post-effective amendment as soon as notified of the matters to be
incorporated in such prospectus supplement or post-effective amendment;

                  (f) prior to any public offering of Common Stock, register or
qualify or cooperate with the selling Holders, the managing underwriters, if
any, and their respective counsel in connection with the registration or
qualification of such shares for offer and sale under the securities or "blue
sky" laws of such jurisdictions within the United States as any selling Holder
or underwriter reasonably requests in writing and do any and all other acts or
things reasonably necessary or advisable to enable the disposition in such
jurisdictions of the shares of Common Stock covered by the applicable
registration statement; provided that the Company will not be required to
qualify generally to do business in any jurisdiction where it would not
otherwise be required to be so qualified or to take any action which would
subject itself to taxation (other than a nominal amount) in any such
jurisdiction or to general service of process in any jurisdiction where it is
not then so subject;

                                       6
<PAGE>

                  (g) cooperate with the selling Holders and the managing
underwriters, if any, to facilitate the timely preparation and delivery of
certificates representing shares of Common Stock to be sold and not bearing any
restrictive legends; and enable such shares to be in such denominations and
registered in such names as the managing underwriters may request at least two
business days prior to any sale of shares to the underwriters;

                  (h) use its best efforts to cause the shares covered by the
applicable registration statement to be listed or registered with or approved by
any stock exchange or quotation system on which the shares of Common Stock are
then listed and by such governmental agencies or authorities within the United
States as may be reasonably necessary to enable the seller or sellers thereof or
the underwriters, if any, to consummate the disposition of such shares;

                  (i) if any fact contemplated by Section 2.04(c)(E) shall
exist, prepare a supplement or post-effective amendment to the applicable
registration statement or the related prospectus or any document incorporated
therein by reference or file any other required document so that, as thereafter
delivered to the purchasers of the shares of Common Stock being sold thereunder,
such prospectus will not contain any untrue statement of a material fact or omit
to state any material fact necessary to make the statements therein, in light of
the circumstances under which they were made, not misleading;

                  (j) provide a CUSIP number for all shares of Common Stock,  no
later than the effective date of the applicable registration statement;

                  (k) enter into such agreements (including an underwriting
agreement) and take all such other actions in connection therewith in order to
expedite or facilitate the disposition of such shares of Common Stock and in
such connection, whether or not an underwriting agreement is entered into and
whether or not the registration is an underwritten registration: (A) make such
representations and warranties to the holders of such shares and the
underwriters, if any, in form, substance and scope as are customarily made by
issuers to underwriters in primary underwritten offerings; (B) obtain opinions
of counsel to the Company (including counsel which may be an employee of the
Company) and updates thereof which counsel and opinions (in form, scope and
substance) shall be reasonably satisfactory to the managing underwriters, if
any, covering the matters customarily covered in opinions requested by such
holders and underwriters; (C) obtain "cold comfort" letters and updates thereof
from the Company's independent certified public accountants, addressed to the
selling Holders and the underwriters, if any, such letters to be in customary
form and covering matters of the type customarily covered in "cold comforts"
letters to underwriters in connection with primary underwritten offerings; (D)
if any underwriting agreement is entered into, the same shall set forth in full
the indemnification provisions and procedures of Section 2.05 with respect to
all parties to be indemnified pursuant to such Section 2.05; and (E) the Company
shall deliver such documents and certificates as may be reasonably requested by
the Holders of the Common Stock being sold and the managing underwriters, if
any, to evidence compliance with clause (A) hereof and with any customary
conditions contained in the underwriting agreement or other agreement entered
into by the Company. The above shall be done at each closing under such
underwriting or similar agreement or as and to the extent otherwise reasonably
required thereunder;

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                  (l) upon reasonable and timely request, make available for
inspection during normal business hours by a representative of each Holder, any
underwriter participating in any disposition pursuant to a registration
statement and any attorney or accountants retained by such selling Holders 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 such representative,
underwriter, attorney or accountant in connection with such registration
statement; provided, that such Holders, underwriters, attorneys or accountants
execute prior thereto an agreement with the Company that all such records,
information or document shall be kept confidential by such persons unless (A)
disclosure of such records, information or documents is required by law or by
court or administrative order, or (B) such records, information or documents are
or become (but only when they become) generally available to the public other
than as a result of disclosure in violation of this paragraph; and

                  (m) otherwise use its best efforts to comply with all
applicable rules and regulations of the SEC, and make generally available to the
Holders earnings statements satisfying the provisions of Section 1l(a) of the
Securities Act no later than 45 days after the end of any 12-month period (or 90
days, if such period is a fiscal year) (A) commencing at the end of any fiscal
quarter in which shares of Common Stock or Equity Securities are sold to
underwriters in an underwritten offering, or (B) if not sold to underwriters in
such an offering beginning with the first month of the Company's first fiscal
quarter commencing after the effective date of the registration statement, which
statements shall cover such 12-month periods.

                  The Company may require each Holder who is a party hereto as
to which any registration is being effected to furnish to the Company such
information and undertakings as it may reasonably request regarding such Holder
and the distribution of such securities as the Company may from time to time
reasonably request in writing.

                  Each Holder who is a party hereto agrees (i) that upon receipt
of any notice from the Company of the happening of any event of the kind
described in Section 2.04(c)(E) such Holder will forthwith discontinue such
Holder's disposition of shares of Common Stock pursuant to the registration
statement relating to such shares until such Holder's receipt of the copies of
the supplemented or amended prospectus contemplated by Section 2.04(i) and, if
so directed by the Company, will deliver to the Company (at the Company's
expense) all copies then in such Holder's possession of the prospectus relating
to such shares current at the time of receipt of such notice and (ii) that such
Holder will immediately notify the Company, at any time when a prospectus
relating to the registration of such shares is required to be delivered under
the Securities Act, of the happening of any event as a result of which
information previously furnished by such Holder to the Company in writing for
inclusion in such prospectus contains 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, in light of the circumstances under which they were
made, not misleading.

                  Section 2.05 Indemnification and Contribution(a) . (a)
Indemnification(i) . (i) In the event of any registration under the Securities
Act of any shares of Common Stock pursuant to this Article 2, the Company hereby
agrees to indemnify and hold harmless each Holder offering or selling such
shares and any underwriter, and their respective officers, directors,
stockholders,

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<PAGE>

members, partners and affiliates, in connection with such offer or sale against
such losses, claims, damages, liabilities, costs or expenses (including
reimbursement for reasonable legal and other expenses) to which any such person
may become subject under the Securities Act or otherwise insofar as such losses,
claims, damages, liabilities, costs or expenses arise out of or are based upon
any untrue statement or alleged untrue statement of any material fact contained
in any registration statement under which such shares were registered under the
Securities Act, any preliminary prospectus, final prospectus or summary
prospectus contained therein, or any amendment or supplement thereto, or any
application or other filing under any "blue sky" or state securities law, or any
omission or alleged omission to state therein a material fact required to be
stated therein or necessary to make the statements therein, in light of the
circumstances under which they were made, not misleading, provided that the
Company shall not be liable in any such case to the extent that any such loss,
claim, damage, liability (or action or proceeding in respect thereof), cost or
expense arises out of or is based upon an untrue statement or omission or
alleged omission made in such registration statement, preliminary prospectus,
final prospectus, summary prospectus, amendment or supplement, or application or
other filing, in reliance upon and in conformity with written information
furnished to the Company through an instrument duly executed by any Holder or
underwriter, specifically for inclusion in such documentation or filing.

(ii) In the event of any registration under the Securities Act of any shares of
Common Stock pursuant to this Article 2, each Stockholder whose shares of Common
Stock are included in such registration hereby agrees to indemnify and hold
harmless, (but only up to an amount, with respect to such Stockholder, not in
excess of the net proceeds realized by such Stockholder from the sale of its
shares of Common Stock registered pursuant to such registration statement), the
Company and its officers, directors, stockholders and affiliates, and any
underwriter, and their respective officers, directors, stockholders and
affiliates, in connection with such offer or sale against such losses, claims,
damages, liabilities, costs or expenses (including reimbursement for reasonable
legal and other expenses) to which any such person may become subject under the
Securities Act or otherwise insofar as such losses, claims, damages,
liabilities, costs or expenses arise out of or are based solely upon any untrue
statement or alleged untrue statement of any material fact contained in any
registration statement under which such shares were registered under the
Securities Act, any preliminary prospectus, final prospectus or summary
prospectus contained therein, or any amendment or supplement thereto, or any
application or other filing under any "blue sky" or state securities law, or any
omission or alleged omission to state therein a material fact required to be
stated therein or necessary to make the statements therein, in light of the
circumstances under which they were made, not misleading, to the extent that
such untrue statement or alleged untrue statement or omission or alleged
omission made in such registration statement, any such preliminary prospectus,
final prospectus, summary prospectus, amendment or supplement, or application or
other filing, is contained in any written information furnished to the Company
through an instrument duly executed by such Stockholder specifically for
inclusion in such documentation or filing.

                  (b) Contribution. (i) If the indemnification provided for in
Section 2.05(a) is unavailable to persons to be indemnified pursuant thereto in
respect of any losses, claims, damages, liabilities, costs or expenses referred
to therein, then the Company, in lieu of indemnifying such person, shall
contribute to the amount paid or payable by such person as a result of such
losses, claims, damages, liabilities, costs or expenses, in such proportion as
is

                                       9
<PAGE>

appropriate to reflect the relative fault of the Company and such persons in
connection with the actions which resulted in such losses, claims, damages,
liabilities, costs or expenses, as well as any other relevant equitable
considerations. The relative fault of the Company and such persons shall be
determined by reference to, among other things, whether any action in question,
including any untrue or alleged untrue statement of a material fact or omission
or alleged omission to state a material fact, has been made by, or relates to
information supplied by, the Company or such persons, and the parties' relative
intent, knowledge, access to information and opportunity to correct or prevent
such action. The amount paid or payable by a party as a result of the losses,
claims, damages, liabilities, costs and expenses referred to above shall be
deemed to include any legal or other fees or expenses reasonably incurred by
such party in connection with any investigation or proceeding.

                  (ii)              The parties  hereto  agree that it would not
                                    be  just  and   equitable  if   contribution
                                    pursuant  to  this   Section   2.05(b)  were
                                    determined by pro rata  allocation or by any
                                    other  method of  allocation  which does not
                                    take account of the equitable considerations
                                    referred  to in  the  immediately  preceding
                                    paragraph. Notwithstanding the provisions of
                                    this Section 2.05(b),  an indemnified person
                                    shall  not be  required  to  contribute  any
                                    amounts in excess of the amount by which the
                                    total  price at which  the  shares of Common
                                    Stock were sold by such  indemnified  person
                                    and  distributed  to the public  exceeds the
                                    amount of any damages which such indemnified
                                    person has otherwise been required to pay by
                                    reason  of such  untrue  or  alleged  untrue
                                    statement  or omission  or alleged  omission
                                    and    provided,    however,    that    such
                                    Stockholder's  aggregate  liability shall be
                                    limited to the net proceeds realized by such
                                    Stockholder  in  such  offering.  No  person
                                    guilty   of   fraudulent   misrepresentation
                                    (within the meaning of Section  11(f) of the
                                    Securities   Act)  shall  be   entitled   to
                                    contribution  from  any  person  who was not
                                    guilty of such fraudulent misrepresentation.

                  (iii)             If  indemnification  is available under this
                                    Article 2, the Company shall  indemnify each
                                    indemnified   party  to  the   full   extent
                                    provided   herein   without  regard  to  the
                                    relative   fault  of  the   Company  or  the
                                    indemnified  party  or any  other  equitable
                                    consideration  provided  for in this Section
                                    2.05(b).

                  (iv)              In  the  event  that  any  provisions  of an
                                    indemnification  clause  in an  underwriting
                                    agreement  executed  by  or on  behalf  of a
                                    Holder  differs  from a  provision  in  this
                                    Article   2,   such    provision    in   the
                                    underwriting  agreement shall determine such
                                    Holder's rights in respect thereof.

                                  Article III.

                               STOCKHOLDER CONSENT

                  Section 3.01 Consent. Each Stockholder hereby consents to the
inclusion of (x) any First Quarter 2000 Persons, (y) any Prior Piggyback Persons
and (z) any New Purchasers as Holders and Stockholders under this Agreement,
provided, however, that New Purchasers shall

                                       10
<PAGE>

become Holders under this Agreement at such time as may be agreed by the Company
and such New Purchasers. Each First Quarter 2000 Person, Prior Piggyback Person
and New Purchaser shall become a party to this Agreement upon execution of a
counterpart signature page of this Agreement and delivery thereof to the
Company. Each Stockholder hereby consent to the amendment of Schedule I hereto
from time to time to add the name and notice address of a Stockholder when such
Person becomes party to this Agreement.

                  Section 3.02 Amendment. Each Stockholder agrees that if in
connection with the admission of any of the Persons identified in items (x), (y)
and (z) of Section 3.01 above as a party to this Agreement, such Person requests
an amendment to this Agreement which would be beneficial to all Stockholders,
the Company shall be entitled to effect such amendment to this Agreement without
the consent of the Stockholders. Notwithstanding anything set forth in this
Agreement, to the extent that an amendment to any provision of this Agreement
only affects a particular Stockholder, the Company may effect such amendment
without the consent of the other Stockholders.



                                   Article IV.

                                  MISCELLANEOUS

                  Section 4.01 Injunctive Relief. It is acknowledged that it
will be impossible to measure in money the damages that would be suffered if the
parties fail to comply with certain of the obligations imposed on them by this
Agreement, including, without limitation, those obligations set forth in Article
II and that in the event of any such failure, an aggrieved Person will be
irreparably damaged and will not have an adequate remedy at law. Any such Person
shall, therefore, be entitled to injunctive relief and/or specific performance
to enforce such obligations, and if any action should be brought in equity to
enforce any of such provisions of this Agreement, none of the parties hereto
shall raise the defense that there is an adequate remedy at law.

                  Section 4.02 Further Assurances. Each party hereto shall do
and perform or cause to be done and performed all such further acts and things
and shall execute and deliver all such other agreements, certificates,
instruments and documents as any other party hereto reasonably may request in
order to carry out the intent and accomplish the purposes of this Agreement and
the consummation of the transactions contemplated hereby.

                  Section 4.03 Governing Law. This Agreement shall be construed
and enforced in accordance with, and the rights of the parties shall be governed
by, the laws of the State of New York.


                  Section 4.04 Entire Agreement; Amendment; Waiver. This
Agreement (i) contains the entire agreement among the parties hereto with
respect to the subject matter hereof, (ii) supersedes all prior written
agreements and negotiations and oral understandings, if any, with respect
thereto, and (iii) may not be amended or supplemented except by an instrument or
counterparts thereof in writing signed by the Company and a majority in interest
of the Holders

                                       11
<PAGE>

(calculated on a fully diluted basis). No waiver of any term or provision shall
be effective unless in writing signed by the party to be charged and such waiver
shall not be effective as to any other provision of this Agreement.
Notwithstanding the foregoing, no written instrument shall be required to be
signed by any Stockholder in connection with the amendment of Schedule I as
contemplated by Section 3.01.

                  In compliance with and not in limitation of item (ii) above,
to the extent a Prior Piggyback Person becomes party to this Agreement, the
piggyback rights provision set forth below applicable to such Prior Piggyback
Person shall be automatically and expressly superseded by this Agreement:

                  (a)      Registration  Rights Agreement,  dated as of December
                           8, 1997: Section 3
                  (b)      Investors  Agreement,  dated as of January 28,  1999:
                           Article IV
                  (c)      Shareholders  Agreement,  dated as of March 10, 1999:
                           Article IV
                  (d)      Agreement and Plan of Merger  (Triumph  Technologies,
                           Inc.), dated as of November 12, 1999: Article VII
                  (e)      Agreement  and Plan of Merger  (Triumph  Development,
                           Inc.), dated as of November 12, 1999: Article VII
                  (f)      Agreement  and Plan of Merger  (The  Jacobson  Group,
                           Inc.), dated as of December 21, 1999; Article VII.

                  Section 4.05 Binding Effect; Assignment. This Agreement shall
be binding on and inure to the benefit of the parties hereto and, subject to the
terms and provisions hereof, their respective legal representatives, successors
and permitted assigns. The rights granted to a Holder pursuant to this Agreement
may be assigned by such Holder to a transferee or assignee of such Holder in
connection with any transfer or assignment of Equity Securities held by such
Holder representing 25% or more of the Equity Securities initially acquired by
such Holder from the Company.

              Section 4.06 Invalidity of Provision. The invalidity or
unenforceability of any provision of this Agreement in any jurisdiction shall
not affect the validity or enforceability of the remainder of this Agreement in
that jurisdiction or the validity or enforceability of this Agreement, including
that provision, in any other jurisdiction.

                  Section 4.07 Counterparts. This Agreement may be executed
simultaneously in two or more counterparts, all of which taken together shall be
deemed but one and the same instrument.

                  Section 4.08 Notices. All notices and other communications
provided for or given or made hereunder shall be in writing (including delivery
by facsimile transmission) and, unless otherwise provided herein, shall be
deemed to have been given when received by the party to whom such notice is to
be given at its address set forth on Schedule I, or such other address for the
party as shall be specified by notice given pursuant hereto.

                  Any notice to the Company shall be given as follows: at Two
Manhattanville Road, Purchase, New York 10577, Attention: General Counsel, with
a copy to E. Ann Gill, Dewey Ballantine LLP, 1301 Avenue of the Americas, New
York, NY 10019.

                                       12
<PAGE>

                  Section 4.09 Headings. The descriptive headings of the several
paragraphs of this Agreement are inserted for convenience only and do not
constitute part of this Agreement.

                  Section 4.10 Confidentiality. Each Stockholder agrees to keep
confidential any information provided to them by the Company pursuant to this
Agreement and the agreement by which such Stockholder acquired securities of the
Company, provided, however, that (i) any of such information may be disclosed to
any such parties' partners, directors, officers, employees and advisors who need
to know such information (it being understood that such partners, directors,
officers, employees and advisors shall be informed by such party of the
confidential nature of such information and shall be directed to treat such
information confidentially), (ii) any such information may be disclosed
following prior notice if required by subpoena, applicable law or stock exchange
rules; and (iii) any disclosure of such information may be made with respect to
which the Company consents in writing. The provisions of this Section 4.10 shall
not apply to information which (i) is already known to such party, (ii) is or
becomes generally available to the public other than as a result of disclosure
by the partners, directors, officers, employees, agents or advisors of such
party, or (iii) becomes available to such party on a non-confidential basis from
a source other than the Company, provided that such source is not known by such
party to be bound by and obligation of confidentiality or secrecy to the
Company.

                                       13
<PAGE>

                  IN WITNESS WHEREOF, this Agreement has been executed by or on
behalf of each of the parties hereto as of the date first above written.
<PAGE>

                                SIGNATURE PAGE TO
                  THE PIGGYBACK REGISTRATION RIGHTS AGREEMENT
     DATED AS OF JANUARY 27, 2000 AMONG INTERLIANT, INC. AND THOSE CERTAIN
                         STOCKHOLDERS SIGNATORY THERETO



INTERLIANT, INC.

By:   /s/  Bradley Feld
      -----------------
           Bradley Feld
Title: Co-Chairman
      ---------------



DELL USA L.P.
By: Dell Gen. P. Corp.
its General Partner

By:    /s/ Alex C. Smith
       -----------------
           Alex C. Smith
Title: Vice President
       --------------



NETWORK SOLUTIONS, INC.

By:  /s/  James P. Rutt
     ------------------
          James P. Rutt
Title: Chief Executive Officer
       -----------------------



BMC SOFTWARE, INC.

By:  /s/ M. Brinkley Morse
     ---------------------
         M. Brinkley Morse
Title: Senior Vice President
       ---------------------



MATTHEW WOLF

By:  /s/ Matthew Wolf
     ----------------
         Matthew Wolf
<PAGE>

                                SIGNATURE PAGE TO
                  THE PIGGYBACK REGISTRATION RIGHTS AGREEMENT
     DATED AS OF JANUARY 27, 2000 AMONG INTERLIANT, INC. AND THOSE CERTAIN
                         STOCKHOLDERS SIGNATORY THERETO



MICHAEL AUGUST

By:  /s/ Michael August
     ------------------
         Michael August



MATHEW D. WOLF CHILDREN'S TRUST

By:  /s/ Erving Wolf
     ---------------
          Erving Wolf
Title:  Trustee
        -------



ANN WELTCHEK WOLF 1995 MARITAL TRUST

By:  /s/ Erving Wolf
     ---------------
         Erving Wolf
Title:  Trustee
        -------



STEVEN R. MUNROE, ROBERT F. MUNROE, BRAD D. MUNROE
 AND PETER HAWTREY

By:  /s/ Steven R. Munroe
     --------------------
         Steven R. Munroe
Title:  Shareholders Representative
        ---------------------------



PATRICIA K. JACOBSON

By:  /s/ Patricia K. Jacobson
     ------------------------
         Patricia K. Jacobson
<PAGE>

                                SIGNATURE PAGE TO
                  THE PIGGYBACK REGISTRATION RIGHTS AGREEMENT
     DATED AS OF JANUARY 27, 2000 AMONG INTERLIANT, INC. AND THOSE CERTAIN
                         STOCKHOLDERS SIGNATORY THERETO



BARRY H. JACOBSON

By:  /s/ Barry H. Jacobson
     ---------------------
         Barry H. Jacobson



RICHARD W. WEISSBERG

By:  /s/ Richard W. Weissberg
     ------------------------
         Richard W. Weissberg



MICHAEL S. KIRSCHENBAUM

By:  /s/ Michael S. Kirschenbaum
     ---------------------------
         Michael S. Kirschenbaum



ELIZABETH W. REILAND

By:  /s/ Elizabeth W. Reiland
     ------------------------
         Elizabeth W. Reiland



RUSSELL REYNOLDS ASSOCIATES

By:  /s/ Albert Morris
     -----------------
         Albert Morris
<PAGE>

                                   SCHEDULE I

                     NAME AND NOTICE ADDRESS OF STOCKHOLDERS


DELL USA L.P.

c/o Dell Computer Corporation, Mail Stop 8066, One Dell Way, Round Rock, Texas
78682, Attention: Paul Legris; with a copy to Thomas H. Welch, Jr., Vice
President and Deputy General Counsel, Legal Department, Dell Computer
Corporation, Mail Stop 8033, One Dell Way, Round Rock, Texas, 78682.

BMC SOFTWARE, INC.
2101 CityWest Blvd., Houston TX 77042, Attention: Robert H. Whilden, Jr.

NETWORK SOLUTIONS, INC.
505 Huntmar Park Drive, Herndon, Virginia 20170; Attention: General Counsel with
a copy to Song H. Pak, Piper Marbury Rudnick & Wolfe, 1200 Nineteenth St., NW,
Washington, DC 20036-2412.