Filed by Biomatrix, Inc.
                        Pursuant to Rule 425 under the Securities Act of 1933
                                     and deemed filed pursuant to Rule 14a-12
                                       of the Securities Exchange Act of 1934

                                         Subject Company: Genzyme Corporation

                                             Registration File No.: 333-34972


                                     * * * *

Investors are urged to read the joint proxy statement/prospectus relating to
the transaction described below because it contains important information.
The joint proxy statement/prospectus, along with the documents incorporated
by reference into that document, may be obtained free of charge at the
Securities and Exchange Commission's website (www.sec.gov). The joint proxy
statement/prospectus and these other documents may also be obtained for free
from Genzyme or Biomatrix. Requests to Genzyme should be directed to Genzyme
Corporation, One Kendall Square, Building 1400, Cambridge, Massachusetts
02139, Attn: Investor Relations, (617) 252-7500, or you can access documents
on its website (www.genzyme.com). Requests to Biomatrix should be directed to
Biomatrix, Inc. 65 Railroad Avenue, Ridgefield, New Jersey 07657, Attn:
Investor Relations, (201) 945-9550, or you can access the documents on its
website (www.biomatrix.com). Genzyme, Biomatrix, their directors, certain of
their executive officers, and certain of their other employees may be
considered participants in the solicitation of proxies in connection with the
proposed creation of Genzyme Biosurgery. Information concerning these
individuals is contained in the joint proxy statement/prospectus filed with
the Securities and Exchange Commission, which remains subject to amendment.

                                     * * * *

TITLE: Genzyme and Biomatrix Announce Registration Statement for Genzyme
Biosurgery Declared Effective by SEC

DATE: November 6, 2000

Genzyme Corp. and Biomatrix, Inc. (NYSE: BXM) announced on November 6, 2000 that
the Securities and Exchange Commission (SEC) has declared effective the
registration statement for the merger of Genzyme and Biomatrix and for the
planned formation of Genzyme Biosurgery, a new Genzyme division.

A joint proxy statement/prospectus will be mailed on November 9 to holders of
Biomatrix stock and to holders of each of Genzyme Corp.'s four tracking stocks.
The record date for Biomatrix shareholders is November 2 and for Genzyme
shareholders the record date is October 25.

Biomatrix will hold a special meeting of its shareholders on December 7, 2000 at
the Marriott at Glenpointe, 100 Frank W. Burr Boulevard, Teaneck, New Jersey, to
obtain the required approvals for Biomatrix's merger with Genzyme. Upon
completion of the merger, the business of




Biomatrix will be combined with the businesses of Genzyme Tissue Repair and
Genzyme Surgical Products to form Genzyme Biosurgery, a new division of Genzyme
Corp.

Genzyme will hold a special meeting of its shareholders on December 15, 2000 at
The Residence Inn, 6 Cambridge Center, Cambridge, Massachusetts. Holders of each
of Genzyme Corp.'s four tracking stocks will be asked to vote to approve a
charter amendment creating Genzyme Biosurgery stock, a new Genzyme Corp.
tracking stock, and eliminating Genzyme Tissue Repair stock (Nasdaq: GZTR) and
Genzyme Surgical Products stock (Nasdaq: GZSP).

The boards of directors of both Genzyme Corp. and Biomatrix have unanimously
approved the merger. Dr. Endre Balazs and three other executive officers of
Biomatrix have agreed to vote their Biomatrix shares, totaling approximately 36
percent of the outstanding shares, in favor of the transaction.

Genzyme intends to list Genzyme Biosurgery stock for trading on the Nasdaq
National Market under the symbol GZBX following completion of the merger and
recapitalization, which is expected to be completed this year. Upon formation,
Genzyme Biosurgery will have approximately 35 million shares outstanding.

"When formed, Genzyme Biosurgery will represent a powerful business in the
growing biosurgical marketplace," stated Duke Collier, president of Genzyme
Surgical Products, who will become president of Genzyme Biosurgery. "We believe
that the combination of Biomatrix's product development expertise and Genzyme's
commercialization infrastructure will build significant value more rapidly than
each enterprise could achieve on its own."

What Shareholders Will Receive

Under the terms of a definitive merger agreement, Genzyme Biosurgery will be
formed by combining Genzyme Tissue Repair, Genzyme Surgical Products and
Biomatrix. Holders of Genzyme Tissue Repair stock will receive 0.3352 of a share
and holders of Genzyme Surgical Products stock will receive 0.6060 of a share of
Genzyme Biosurgery stock for each share of their stock.

Under the merger agreement, Genzyme has agreed to pay cash at $37 per share for
up to 28.38 percent of the outstanding shares of Biomatrix common stock and to
exchange Genzyme Biosurgery stock on a one-for-one basis for 71.62 percent of
the outstanding shares of Biomatrix common stock. The cash portion of the merger
consideration is limited to approximately $245 million, but may be reduced to
accommodate the exercise of appraisal rights, and for tax purposes to assure
that at least 45 percent of the total consideration is Genzyme Biosurgery stock.

Biomatrix will send its shareholders an election form on which they will be able
to indicate their preference for the standard consideration--a fixed combination
of cash and stock; a cash consideration; and/or a stock consideration. Assuming
no adjustment to the aggregate cash consideration occurs, Biomatrix shareholders
who





select the standard consideration will receive $37 in cash for 28.38 percent of
their Biomatrix shares and will receive one share of Genzyme Biosurgery stock
for one share of Biomatrix stock for 71.62 percent of their Biomatrix shares.

If Biomatrix shareholders elect in the aggregate to receive cash for more than
the available cash consideration, the amount of cash distributed to shareholders
who make cash elections will be reduced on a prorated basis and offset with
shares of Genzyme Biosurgery. Conversely, if Biomatrix shareholders elect in the
aggregate to receive more shares of Genzyme Biosurgery stock than are available,
the number of shares of Genzyme Biosurgery stock distributed to shareholders who
make stock elections will be reduced on a prorated basis and offset with cash.
Therefore, the consideration received by a Biomatrix shareholder may differ from
the shareholder's expressed preference, except in the case of those shareholders
who elect the standard consideration--assuming no adjustment to the aggregate
cash consideration is necessary.

Upon completion of the merger, Biomatrix shareholders will own approximately 47
percent of the outstanding Genzyme Biosurgery shares, holders of Genzyme Tissue
Repair stock will own approximately 27 percent, and holders of Genzyme Surgical
Products stock will own approximately 26 percent.

About Genzyme Biosurgery

Genzyme Biosurgery will represent a powerful new enterprise in the biosurgery
field with a portfolio of 24 marketed products, a pipeline of innovative
products, leading technology platforms and scientific team to drive its R&D
programs, and sufficient financial resources to expand its presence in an
exciting and rapidly growing global business.

Once established, the new division will have approximately 1,300 employees; six
dedicated manufacturing facilities; global clinical and regulatory capabilities;
an extensive intellectual property portfolio; several established sales
organizations in focused surgical markets in both the United States and Europe;
and marketing and distribution agreements with a number of large, multinational
healthcare companies.

Genzyme Corporation is a biotechnology company that develops and markets
innovative products and services designed to address significant unmet medical
needs. Genzyme Surgical Products, a division of Genzyme Corp., develops and
markets a portfolio of devices, biomaterials, and biotherapeutics primarily for
the cardiovascular and general surgery markets. Genzyme Tissue Repair, a
division of Genzyme Corp., is a leading developer of biological products for the
treatment of orthopedic injuries such as cartilage damage and severe burns.

Biomatrix, Inc., headquartered in Ridgefield, New Jersey is an international
biomedical company that develops, manufactures and commercializes elastoviscous
products made from proprietary polymers called hylans, which are derivatives of
the naturally occurring substance, hyaluronan, and are used in a variety of
therapeutic medical applications and in skin care products.




This press release contains forward-looking statements, including statements
concerning the mailing of a joint proxy statement/prospectus, the holding of
Biomatrix and Genzyme shareholder meetings to vote on the formation of Genzyme
and Biosurgery and the Biomatrix merger, the formation of Genzyme Biosurgery and
the consummation of the merger with Biomatrix, the creation of a new publicly
traded stock for Genzyme Biosurgery, the future growth and success of Genzyme
Biosurgery and Genzyme Biosurgery's products, the growth of the biosurgery
market and Genzyme Biosurgery's penetration of that market, the sufficiency of
the cash and other resources of Genzyme Biosurgery, and the ability of Genzyme
Biosurgery to expand its business. Actual results may differ materially
depending on many factors including the accuracy of information about the
biosurgery market, the competitive environment for the biosurgery market, market
acceptance of Genzyme Biosurgery's products and services, the enrollment rate
for clinical trials, the ability to successfully complete preclinical and
clinical development of products, the actual safety and efficacy of products,
the timing and content of submissions to and decisions by the FDA and other
regulatory authorities, conditions in the financial markets relevant to the
proposed creation of Genzyme Biosurgery, the receipt of all approvals necessary
to complete the creation of Genzyme Biosurgery and the merger with Biomatrix,
the operational integration associated with the transactions and other risks
generally associated with transactions of this type.

This press release is not a substitute for the joint proxy statement/prospectus.
We urge investors to read that document because it contains important
information. The joint proxy statement/prospectus and the documents incorporated
by reference may be obtained free of charge at the SEC's website
(http://www.sec.gov) or by contacting Genzyme or Biomatrix.