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                                                                    EXHIBIT 4.2



                         CONTRACT FOR THE SALE OF SHARES
                                     BETWEEN
                       TELEFONICA EMPRESAS CTC CHILE S.A.
                                       AND
                        INVERSIONES SANTA ISABEL LIMITADA

In Santiago, Chile, on September 26, 2002, before me, RAUL UNDURRAGA LASO,
attorney, of this domicile, MacIver 225, Suite 302, Notary Public of Santiago,
Titular of the 29th Notarial office, there appeared:

1. TELEFONICA EMPRESAS CTC CHILE S.A., Taxpayer Identification Number
90.430.000-4, represented by Mr. CLAUDIO MUNOZ ZUNIGA, Chilean, married, civil
industrial engineer, passport number 9.618.122-1, both domiciled at Avenida
Providencia 111, 29th floor, borough of Providencia for these purposes,
hereinafter also called "Telefonica" or the "Seller," as one party;

2. INVERSIONES SANTA ISABEL LIMITADA, Taxpayer Identification Number
79.822.680-0, represented, as shall be evidenced, by Mr. ANDRES NAVARRO
HAEUSSLER, Chilean, married, civil engineer, passport number 5.078.702-8, both
domiciled at Teatinos 574, Santiago, for these purposes, hereinafter also called
"Santa Isabel."

The parties are of age, evidenced their identities by the aforesaid identity
cards and stated that they have agreed to the following purchase agreement.

RECITALS

1. Whereas Telefonica is currently the sole owner and holder of forty-nine
thousand shares in SOCIEDAD NACIONAL DE PROCESAMIENTO DE DATOS S.A., hereinafter
"Sonda" or the "Company," which is a closed corporation incorporated and
organized under the laws of the Republic of Chile. Said holding is equal to
forty-nine percent of the shares validly issued by the Company.



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2. Whereas Inversiones Pacifico II Limitada, a company related to Mr. Andres
Navarro H., is currently the sole owner and holder of forty-one thousand shares
in Sonda and Inversiones Atlantico Limitada, a company related to Inversiones
Pacifico II Limitada, is currently the sole owner and holder of ten thousand
shares in Sonda, which, combined with the shares held by Telefonica, constitute
one hundred percent of the subscribed, paid-in and issued shares of the Company,
all in one same series.

3. Whereas Sonda was incorporated as a limited liability company by public deed
executed October 30, 1974, in the Santiago Notarial Office of Mr. Herman
Chadwick. It was transformed into a stock corporation by public deed dated
September 17, 1991, an abstract of which was registered on page 28201 number
14276 of the 1991 Commercial Registry of the Santiago Real Estate Registrar,
published in the Official Gazette on September 24th of the same year;

4. Whereas Inversiones Santa Isabel Limitada declares that it knows the actual
financial, accounting, tax and legal condition of Sonda and therefore expressly
releases Telefonica from the obligation to make representations, except for the
liability that may apply to it in particular regarding the labor lawsuits listed
in the document signed on the date herewith by Inversiones Pacifico II Limitada
et al and Telefonica CTC Chile S.A., which is deemed a part hereof for all legal
purposes.

FIRST: Sale of Shares. Telefonica, duly represented by Mr. Claudio Munoz Zuniga,
hereby sells, assigns and transfers fourteen thousand shares in Sonda, equal to
fourteen percent of the share capital, to Santa Isabel, which are purchased,
acquired and accepted by Mr. Andres Navarro Haeusseler on behalf thereof. The
total purchase price of the aforesaid shares is eleven billion seven hundred
sixty-one million fifty-six thousand six hundred two pesos, equal in pesos,
local currency, to seven hundred fifteen thousand one hundred twenty Unidades de
Fomento that Santa Isabel pays in this act, at once, in cash. Telefonica
declares receipt of such sum to its full satisfaction. Telefonica hereby
delivers the certificates to Santa Isabel for the shares that have been acquired
and paid thereby hereunder, free and clear of liens. Santa Isabel declares
receipt thereof to its full satisfaction.

SECOND: Representations by the Parties. The Parties declare the following for
purposes hereof:


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Corporate Authorizations: Both the execution of this agreement as well as
performance of all obligations herein contained are within the authority of the
Parties, have been approved by the management of each thereof and constitute a
valid and binding agreement.

No Breach: The execution and performance of this agreement by both parties do
not breach nor conflict with the bylaws thereof nor those of the Company nor
breach or violate any legal, administrative or regulatory rule or judicial
resolution notified to, and binding upon, the parties.

THIRD: Miscellaneous. Expenses: All fees, taxes, expenses and costs derived from
this agreement shall be paid equally by both parties.

Governing Law:  This agreement is governed by the laws of the Republic of Chile.

Domicile. For all legal purposes derived herefrom, the parties elect their
domicile as the city and borough of Santiago.

Authorities: The authority of the representative of Telefonica Empresas CTC
Chile S.A. is evidenced in the public deed dated July 30, 2002, notarized by Mr.
Alvaro Bianchi Rosas, Notary Public of Santiago. The authority of the
representative of Inversiones Santa Isabel Limitada is evidenced in the public
deed executed June 21, 1996 in the Santiago Notarial Office of Mr. Ivan
Torrealba. Such authorities are not inserted as they are known to the
authenticating Notary.

NOTARIAL CERTIFICATION: The authenticating Notary does certify that this public
deed is executed in accordance with the Law.


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In witness whereof, the parties sign after reading. A copy is issued. I attest.



                            ------------------------
                              CLAUDIO MUNOZ ZUNIGA
                     for TELEFONICA EMPRESAS CTC CHILE S.A.





                            -------------------------
                            ANDRES NAVARRO HAEUSSLER
                      for INVERSIONES SANTA ISABEL LIMITADA


THEY SIGNED BEFORE ME AT PROVIDENCIA 111, 24TH FLOOR, SANTIAGO, SEPTEMBER 26,
2002.




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