PRESS RELEASE

[IDEXX LOGO] IDEXX Laboratories, Inc.

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One IDEXX Drive, Westbrook, Maine 04092 USA
Telephone 207-856-0300
Facsimile 207-856-0346
Telex 9103807069

FOR IMMEDIATE RELEASE

IDEXX LABORATORIES, INC. ADOPTS SHAREHOLDER RIGHTS PLAN

WESTBROOK, MAINE, DECEMBER 17, 1996. IDEXX Laboratories, Inc. (NASDAQ -
IDXX) announced today that its Board of Directors has adopted a Shareholder
Rights Plan in which preferred stock purchase rights will be distributed on
December 30, 1996 as a dividend at the rate of one Right for each share of the
Company's Common Stock outstanding as of the close of business on that date.

The Rights Plan is designed to enable all stockholders of IDEXX to
realize the long-term value of their investment in the Company. David E. Shaw,
Chairman of the Company's Board of Directors and Chief Executive Officer, said
the Rights Plan "will not restrict consideration by the Board of any offer on
terms favorable to all stockholders, but is intended to protect the interests of
stockholders in the event the Company is confronted with coercive or unfair
takeover tactics." He noted that such tactics include "a partial or two-tiered
tender offer that does not treat all stockholders equally, the acquisition in
the open market or otherwise of shares constituting control without offering
fair value to all stockholders, or other abusive takeover tactics." "These
tactics," he added, "can unfairly pressure stockholders, squeeze them out of
their investment without giving them any real choice, and deprive them of the
full value of their shares."

Each Right will entitle the holders of the Company's Common Stock to
purchase one one-thousandth of a share of a new series of junior participating
preferred stock of the Company at an exercise price of $200. The Rights will be
exercisable only if a person or group has acquired beneficial ownership of 20%
or more of the Common Stock of the Company or announces a tender or exchange
offer that would result in such person or group owning 30% or more of the Common
Stock of the Company.

If any person becomes the beneficial owner of 20% or more of the shares
of Common Stock of the Company, except pursuant to a tender or exchange offer
for all shares at a fair price as determined by the outside Board members, each
Right not owned by the 20% or more stockholder will enable its holder to
purchase that number of shares of the Company's Common Stock which equals the
exercise price of the Right divided by one-half of the current market price of
such Common Stock at the date of the occurrence of the event. In addition, if
the Company is involved in a merger or other business combination transaction
with another person or group in





which it is not the surviving corporation or in connection with which its Common
Stock is changed or converted, or it sells or transfers 50% or more of its
assets or earning power to another person, each Right that has not previously
been exercised will entitle its holder to purchase that number of shares of
Common Stock of such other person which equals the exercise price of the Right
divided by one-half of the current market price of such Common Stock at the date
of the occurrence of the event.

The Company will generally be entitled to redeem the Rights at $0.01
per Right at any time until the tenth business day following public announcement
that a 20% stock position has been acquired and in certain other circumstances.
The Rights will expire on December 30, 2006 unless earlier redeemed or
exchanged.

IDEXX Laboratories, Inc. is a world leader in providing innovative
diagnostic products for a broad range of veterinary, food and environmental
testing applications. The Company currently sells over 100 products to customers
in more than 50 countries, and is headquartered in Westbrook, Maine.


FOR FURTHER INFORMATION CONTACT:

Richard B. Thorp
General Counsel
IDEXX Laboratories, Inc.
One IDEXX Drive
Westbrook, Maine 04092
Phone: (207) 856-0426
Fax: (207) 856-0347