EXHIBIT 4.3 AMENDED AND RESTATED INVESTORS RIGHTS AGREEMENT

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                                                                     EXHIBIT 4.3

                 AMENDED AND RESTATED INVESTORS RIGHTS AGREEMENT

          THIS AMENDED AND RESTATED INVESTORS RIGHTS AGREEMENT (the "AGREEMENT")
is made and dated as of the 22nd day of December 2000 by and among the
individuals listed as Common Stockholders on Schedule A hereto (the "COMMON
STOCKHOLDERS"), the individuals and entities listed as Other Stockholders on
Schedule A hereto (the "OTHER STOCKHOLDERS"), the entity listed as a Series 1
Stockholder on Schedule A hereto (the "SERIES 1 STOCKHOLDER") and the
individuals and entities listed as Series A Stockholders on Schedule A hereto
(the "SERIES A STOCKHOLDERS") and SynchronOSS Technologies, Inc., a Delaware
corporation (the "COMPANY").

                                   BACKGROUND

          WHEREAS, the Common Stockholders are holders of shares of outstanding
Common Stock of the Company, $0.0001 par value per share (the "COMMON STOCK");

          WHEREAS, certain of the Series A Stockholders (the "SUBSEQUENT SERIES
A STOCKHOLDERS") are party to that certain Series A Preferred Stock Purchase
Agreement (the "PURCHASE AGREEMENT"), dated the date hereof, pursuant to which
they are acquiring shares of the Company's Series A Preferred Stock (the "SERIES
A PREFERRED STOCK");

          WHEREAS, the Common Stockholders, the Other Stockholders, certain of
the Series A Stockholders and the Company are party to that certain Investors
Rights Agreement, dated as of November 13, 2000 (the "PRIOR AGREEMENT"), entered
into in connection with the issuance of shares of Series A Preferred Stock,
which they now desire to amend and restate in certain respects;

          WHEREAS, the Subsequent Series A Stockholders obligations under the
Purchase Agreement are conditioned upon the execution and delivery of this
Amended and Restated Agreement.

          NOW, THEREFORE, in consideration of the mutual promises and covenants
set forth in this Agreement, and intending to be legally bound, the parties
agree as follows:

SECTION 1. DEFINITIONS.

          1.1 "AFFILIATE" means, with respect to any specified person, (i) any
other person that owns (directly or indirectly), individually or as part of a
group (as determined pursuant to Rule 13d-5 under the Securities Exchange Act of
1934, as amended (the "Act")), greater than fifty percent (50%) of the voting
stock or other capital interest of such specified person, (ii) any other person
of whom greater than fifty percent (50%) of the voting stock or other capital
interest is owned by (directly or indirectly), individually or as part of a
group (as determined pursuant to Rule 13d-5 under the Act, by such person, and
(iii) any other person controlling, controlled by or under common control with
such person.

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          1.2 "FULLY DILUTED COMMON STOCK" shall mean the Company's outstanding
Common Stock and shares of Common Stock issued or issuable upon conversion of
the Company's outstanding preferred stock, or upon exercise of outstanding
rights, options and warrants to acquire Common Stock.

          1.3 "QUALIFIED IPO" shall mean a firm commitment initial public
offering by t he Company pursuant to a registration statement under the
Securities Act of 1933 (i) with an aggregate offering price of at least Twenty
Million Dollars ($20,000,000) and (ii) at a per share price equal to at least
$8.70 (subject to adjustment for stock dividends, recapitalizations, splits and
similar events).

SECTION 2. SALES BY THE COMMON STOCKHOLDERS.

          2.1 Rights of Refusal.

               (a) Transfer Notice. If at any time any Common Stockholder (the
"SELLING STOCKHOLDER") proposes to transfer any shares of the Company's Common
Stock ("EQUITY SECURITIES") to one or more third parties pursuant to an
understanding with such third parties (a "TRANSFER"), then the Selling
Stockholder shall give to the Company, and to each of the other Common
Stockholders and Series A Stockholders, if any (together, the "NON-SELLING
STOCKHOLDERS"), written notice of the Selling Stockholder's intention to make
the Transfer (the "TRANSFER NOTICE"), which Transfer Notice shall include (i) a
description of the Equity Securities to be transferred (the "OFFERED SHARES"),
(ii) the identity of the prospective transferee(s) and (iii) the consideration
and the material terms and conditions upon which the proposed Transfer is to be
made. The Transfer Notice shall certify that the Selling Stockholder has
received a firm offer from the prospective transferee(s) and in good faith
believes a binding agreement for the Transfer is obtainable on the terms set
forth in the Transfer Notice. The Transfer Notice shall also include a copy of
any written proposal, term sheet or letter of intent or other agreement relating
to the proposed Transfer.

               (b) Company's Option. The Company shall have an option for a
period of ten (10) days from receipt of the Transfer Notice to elect to purchase
all or a portion of the Offered Shares at the same price and subject to the same
material terms and conditions as described in the Transfer Notice. The Company
may exercise such purchase option and thereby purchase all (or a portion of) the
Offered Shares by notifying the Selling Stockholder in writing before expiration
of the such ten (10) day period as to the number of such Offered Shares which it
wishes to purchase. If the Company gives t he Selling Stockholder notice that it
desires to purchase such shares, then payment for the Offered Shares shall be by
check, wire transfer or cancellation of indebtedness, against delivery of the
Offered Shares to be purchased at a place agreed upon between the parties and at
the time of the scheduled closing therefor, which shall be no later than
forty-five (45) days after the Company's receipt of the Transfer Notice, unless
the Transfer Notice contemplated a later closing with the prospective third
party transferee(s). If the Company fails to purchase all of the Offered Shares
by exercising the option granted in this Section 2.1(b) within the period
provided, the Offered Shares which the Company has not elected to purchase shall
be subject to the option granted to the Non-Selling Stockholders pursuant to
this Agreement.


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               (c) Additional Transfer Notice. Subject to the Company's right
set forth in Section 2.1(b), if at any time the Selling Stockholder proposes a
Transfer, then, after the Company has declined to purchase all, or a portion of,
the Offered Shares, the Selling Stockholder shall give each Non-Selling
Stockholder an "ADDITIONAL TRANSFER NOTICE" which shall include all of the
information and certifications required in a Transfer Notice and shall
additionally identify the Offered Shares which the Company has declined to
purchase (the "REMAINING SHARES") and briefly describe Non-Selling Stockholders'
rights of first refusal and co-sale rights with respect to the proposed
Transfer.

               (d) Non-Selling Stockholders' Option. The Non-Selling
Stockholders shall have an option for a period of twenty (20) days from the
Non-Selling Stockholder's receipt of the Additional Transfer Notice to elect to
purchase their respective pro rata shares of the Remaining Shares at the same
price and subject to the same material terms and conditions as described in the
Additional Transfer Notice. Each Non-Selling Stockholder may exercise such
purchase option and thereby purchase all or any portion of his, her or its pro
rata share (with any reallotments as provided below) of the Remaining Shares, by
notifying the Selling Stockholder and the Company in writing, before expiration
of the twenty (20) day period as to the number of such shares which he, she or
it wishes to purchase (including any reallotment). Each Non-Selling
Stockholder's pro rata share of the Remaining Shares shall be a fraction of the
Remaining Shares, of which the number of shares of Common Stock (including
shares of Common Stock issuable upon conversion of Preferred Stock) owned by
such Non-Selling Stockholder on the date of the Transfer Notice shall be the
numerator and the total number of shares of Common Stock (including shares of
Common Stock issuable upon conversion of the Company's Preferred Stock) held by
all Non-Selling Stockholders on the date of the Transfer Notice shall be the
denominator.

          2.2 Right of Co-Sale.

               (a) To the extent t he Company and t he Non-Selling Stockholders
do not exercise their respective rights of refusal as to all of the Offered
Shares pursuant to Section 2.1, then each Non-Selling Stockholder (a "CO-SELLING
STOCKHOLDER") notifying t he Selling Stockholder in writing within thirty (30)
days after receipt of the Transfer Notice referred to in Section 2.1(a), shall
have the right to participate in such sale of Equity Securities on the same
terms and conditions as specified in the Transfer Notice. Such Co-Selling
Stockholder's notice to the Selling Stockholder shall indicate the number of
shares of Equity Securities the Co-Selling Stockholder wishes to sell under his,
her or its right t o participate. To t he extent one or more of t he Non-Selling
Stockholders exercise such right of participation in accordance with the terms
and conditions set forth below, the number of shares of Equity Securities that
the Selling Stockholder may sell in the Transfer shall be correspondingly
reduced.

               (b) Each Co-Selling Stockholder may sell all or any part of t hat
number of shares of Equity Securities equal to the product obtained by
multiplying (i) the aggregate number of shares of Equity Securities covered by
the Transfer Notice by (ii) a fraction, the numerator of which is the number of
shares of Common Stock (including shares of Common Stock issuable upon
conversion of Preferred Stock) owned by the Co-Selling Stockholder on the date
of the Transfer Notice and the denominator of which is the total number of
shares of Common Stock (including shares of Common Stock issuable upon
conversion of Preferred


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Stock) owned by the Selling Stockholder and all of the Co-Selling Stockholders
on the date of the Transfer Notice.

          2.3 Non-Exercise of Rights. To the extent that the Company and the
Non-Selling Stockholders have not exercised their rights to purchase the Offered
Shares or the Remaining Shares within the time periods specified in Section 2.1
and the Non-Selling Stockholders have not exercised their rights to participate
in the sale of the Offered Shares or the Remaining Shares within the time
periods specified in Section 2.2, the Selling Stockholder shall have a period of
thirty (30) days from the expiration of such rights in which to sell the Offered
Shares or the Remaining Shares, as the case may be, upon terms and conditions
(including the purchase price) no more favorable than those specified in the
Transfer Notice to the third-party transferee(s) identified in the Transfer
Notice. In the event Selling Stockholder does not consummate the sale or
disposition of the Remaining Shares within the thirty (30) day period from the
expiration of these rights, the Company's first refusal rights and the
Non-Selling Stockholders' first refusal rights and co-sale rights shall continue
t o be applicable to any subsequent disposition of the Offered Shares or the
Remaining Shares by Selling Stockholder until such right lapses in accordance
with the terms of this Agreement. Furthermore, the exercise or non-exercise of
the rights of the Company and the Non-Selling Stockholders under this Section 2
to purchase Equity Securities from t he Selling Stockholder or t o participate
in sales of Equity Securities by the Selling Stockholder shall not adversely
affect their rights to make subsequent purchases from the Selling Stockholder of
Equity Securities or subsequently participate in sales of Equity Securities by
the Selling Stockholder.

          2.4 Delivery of Shares. Each Co-Selling Stockholder shall effect it s
participation in a sale on a co-sale basis by promptly delivering to the Selling
Stockholder for transfer to the prospective purchaser one or more certificates,
properly endorsed for transfer, which represent: (a) that number of shares of
Common Stock which such Co-Selling Stockholder elects to sell; or (b) that
number of shares of Preferred Stock which is at such time convertible into the
number of shares of Common Stock which such Co-Selling Stockholder elects t o
sell on a co-sale basis; provided, however, that if the prospective purchaser
objects to the delivery of Preferred Stock in lieu of Common Stock, such
Co-Selling Stockholder shall convert such Preferred Stock into Common Stock and
deliver Common Stock as provided in subparagraph 2.4(a) above. The Company
agrees to make any such conversion concurrent with the actual transfer of such
shares to the purchaser.

          2.5 Closing. The stock certificate or certificates, if any, that the
Co-Selling Stockholder delivers to the Selling Stockholder pursuant to Section
2.4 shall be transferred to the prospective purchaser in consummation of the
sale of the Offered Shares pursuant to the terms and conditions specified in the
Transfer Notice, and t he Selling Stockholder shall concurrently therewith remit
to such Co-Selling Stockholder t hat portion of t he sale proceeds to which such
Co-Selling Stockholder is entitled by reason of its participation in such sale.
To the extent that any prospective purchaser, or purchasers, prohibits such
assignment or otherwise refuses to purchase shares or other securities from a
Co-Selling Stockholder exercising its rights of co-sale hereunder, the Selling
Stockholder shall not sell to such prospective purchaser or purchasers any
Offered Shares unless and until, simultaneously with such sale, the Selling
Stockholder shall purchase such shares or other securities from such Co-Selling
Stockholder. To the extent that a Non-Selling Stockholder elects to purchase any
of the Offered Shares covered in the Transfer


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Notice directly from the Selling Stockholder, then such Selling Stockholder
shall within ninety (90) days of the date of the Transfer Notice (or, if
earlier, simultaneous with the consummation of the sale of the Offered Shares
pursuant to the terms and conditions specified in the Transfer Notice) deliver
certificate(s) for such shares to such acquiring Non-Selling Stockholders who
shall deliver to the Selling Stockholder the consideration of the type and on
the terms set forth in the Transfer Notice.

          2.6 McCormick Assignment. James McCormick ("McCormick") hereby agrees
that, pursuant to Section 6 of each the Employee Stock Transfer Agreements (as
defined below), he will assign the right of first refusal granted therein (to
the extent not exercised by McCormick) first to the Company and second to the
Series A Stockholders with sufficient time to each such party to permit the
exercise thereof; provided that, in the case of the Series A Stockholders,
notice of such assignment by McCormick shall be given to the Series A
Stockholders no less than ten (10) days prior to the expiration of such right.
For purposes of this Section 2.6, "Employee Stock Transfer Agreements" shall
mean those certain agreements, each dated October 5, 2000, between James
McCormick and each of James Mortenson, Peter McCormick, Charles Machlin, Darrell
Sagehorn and Richard McCormick.

SECTION 3. EXEMPT TRANSFERS.

          3.1 Certain Transfers. The provisions of Sections 2.1 through 2.5
shall not apply to: (a) the transfer of Equity Securities by a Common
Stockholder in one or more transactions representing an aggregate of 5% or less
of the total number of Equity Securities held by such Common Stockholder as of
the date hereof; (b) any transfer of Equity Securities to the ancestors,
descendants or spouse of a Common Stockholder, or to trusts, family limited
partnerships or similar estate planning entities for the benefit of such persons
including such Common Stockholder; and (c) any bona fide gift, provided that, in
any such case the Common Stockholder gives the Company and each of the members
of the Board of Directors of the Company designated by the Series A Stockholders
prior written notice of such transfer or gift and the transferee or donee shall
first furnish the Company with a written agreement to be bound by and comply
with all provisions of Section 2 as well as the terms of any other restrictive
agreement to which such Equity Securities are subject. Such transferred Equity
Securities shall remain "Equity Securities" hereunder, and such pledgee,
transferee or donee shall be treated as a "Common Stockholder" for purposes of
this Agreement.

          3.2 Public Offering; Company Transfers. Notwithstanding the foregoing,
the provisions of Section 2 shall not apply to the sale of any Equity Securities
(a) to the public pursuant to a registration statement filed with, and declared
effective by, the Securities and Exchange Commission under the Act; or (b) to
the Company.

SECTION 4. PROHIBITED TRANSFERS.

          4.1 Put Option Right. In the event a Common Stockholder should sell
any Equity Securities in contravention of the right of first refusal or co-sale
rights under Section 2 of this Agreement (a "PROHIBITED TRANSFER"), each
Non-Selling Stockholder, in addition to such other remedies as may be available
at law, in equity or hereunder, shall have the put option


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provided below, and the Selling Stockholder shall be bound by the applicable
provisions of such option.

          4.2 Put Option. In the event of a Prohibited Transfer, each
Non-Selling Stockholder shall have the right to sell to the Selling Stockholder
the number of Equity Securities equal to the number of Equity Securities each
Non-Selling Stockholder would have been entitled to transfer to the purchaser
had the Prohibited Transfer under Section 2 hereof been effected pursuant to and
in compliance with the terms hereof. Such sale shall be made on the following
terms and conditions:

               (a) the price per share at which the Equity Securities are to be
sold shall be equal to t he price per share paid by t he purchaser in t he
Prohibited Transfer. The Selling Stockholder shall also reimburse each
Non-Selling Stockholder for any and all fees and expenses, including legal fees
and expenses, incurred pursuant to the exercise or the attempted exercise of t
he Non-Selling Stockholder's rights under Section 2;

               (b) within ninety (90) days after the later of the dates on which
the Non-Selling Stockholder (i) received notice of the Prohibited Transfer or
(ii) otherwise became aware of the Prohibited Transfer, each Non-Selling
Stockholder shall, if exercising the option created hereby, deliver to the
Selling Stockholder the certificate or certificates representing Equity
Securities to be sold, each certificate to be properly endorsed for trans