Filed by Comcast Corporation
                                               Pursuant to Rule 425 under the
                                               Securities Act of 1933 and deemed
                                               filed pursuant to Rule 14a-12
                                               under the Securities Exchange Act
                                               of 1934

                                               Subject Company: AT&T Corp.
                                               Commission File No. 1-1105

                                               Date: July 19, 2001


          The following letter was sent to Comcast employees:


[COMCAST LOGO]


Thursday, July 19, 2001


Dear Comcasters:

          As you may have read in today's newspapers, the AT&T Board of
Directors rejected our proposal to merge with AT&T Broadband. Importantly, the
AT&T Board also said they have decided to delay the vote on their broadband
tracking stock proposal.

          Since our July 8 offer, their shareholders have responded favorably to
our proposal, and AT&T stock has risen dramatically, adding about $14 billion in
market valuation to AT&T. In their press release yesterday, AT&T stated that
management will "explore financial and strategic alternatives." We assume that
we will be part of that process. Consequently, we see this announcement as
positive news for our company.

          During the last ten days we have had dozens of meetings with major
AT&T and Comcast shareholders. During these visits we have been struck by how
positively our company is viewed and how confident investors are in our
operating team. That should make all of you proud to work for Comcast.











          Our proposal is off to a very good start. We appreciate your support
during this process and will keep you updated in the weeks ahead.

Sincerely,


/s/ Brian L. Roberts                        /s/ Stephen B. Burke
Brian L. Roberts                            Stephen B. Burke
President                                   President
Comcast Corporation                         Comcast Cable Communications, Inc.






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   Note: The following notice is included to meet certain legal requirements:

                           FORWARD-LOOKING STATEMENTS

          This filing contains forward-looking statements within the meaning of
the Private Securities Litigation Reform Act of 1995. In some cases, you can
identify those so-called "forward-looking statements" by words such as "may,"
"will," "should," "expects," "plans," "anticipates," "believes," "estimates,"
"predicts," "potential," or "continue," or the negative of those words and other
comparable words. Comcast Corporation ("Comcast") wishes to take advantage of
the "safe harbor" provided for by the Private Securities Litigation Reform Act
of 1995 and you are cautioned that actual events or results may differ
materially from the expectations expressed in such forward-looking statements as
a result of various factors, including risks and uncertainties, many of which
are beyond the control of Comcast. Factors that could cause actual results to
differ materially include, but are not limited to: (1) the businesses of Comcast
and AT&T Broadband may not be integrated successfully or such integration may be
more difficult, time-consuming or costly than expected; (2) expected combination
benefits from the transaction may not be fully realized or realized within the
expected time frame; (3) revenues following the transaction may be lower than
expected; (4) operating costs, customer loss and business disruption, including,
without limitation, difficulties in maintaining relationships with employees,
customers, clients or suppliers, may be greater than expected following the
transaction; (5) the regulatory approvals required for the transaction may not
be obtained on the proposed terms or on the anticipated schedule; (6) the
effects of legislative and regulatory changes; (7) the potential for increased
competition; (8) technological changes; (9) the need to generate substantial
growth in the subscriber base by successfully launching, marketing and providing
services in identified markets; (10) pricing pressures which could affect demand
for Comcast's services; (11) Comcast's ability to expand its distribution; (12)
changes in labor, programming, equipment and capital costs; (13) Comcast's
continued ability to create or acquire programming and products that customers
will find attractive; (14) future acquisitions, strategic partnerships and
divestitures; (15) general business and economic conditions; and (16) other
risks described from time to time in Comcast's periodic reports filed with the
Securities and Exchange Commission (the "Commission").

                             ADDITIONAL INFORMATION

          Subject to future developments, Comcast may file with the Commission
(i) a preliminary proxy statement for solicitation of proxies from the
shareholders of AT&T Corp. ("AT&T") in connection with AT&T's special meeting
which is scheduled to take place in September 2001 and (ii) a registration
statement to register the Comcast shares to be issued in the proposed
transaction. Investors and security holders are urged to read the proxy
statement and registration statement (when and if available) and any other
relevant documents filed with the Commission, as well as any amendments or
supplements to those documents, because they will contain important information.
Investors and security holders may obtain a free copy of the proxy statement and
the registration statement (when and if available) and other relevant documents
at




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the Commission's Internet web site at www.sec.gov. The proxy statement and
registration statement (when and if available) and such other documents may also
be obtained free of charge from Comcast by directing such request to: Comcast
Corporation, 1500 Market Street, Philadelphia, Pennsylvania 19102-2148,
Attention: General Counsel.

          Comcast, its directors and certain other Comcast employees and
advisors may be deemed to be "participants" in Comcast's solicitation of proxies
from AT&T's shareholders. A detailed list of the names, affiliations and
interests of the participants in the solicitation is contained in a filing made
by Comcast with the Commission pursuant to Rule 14a-12 on July 9, 2001.





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