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April 9, 1998          [Letterhead of Cooley Godward LLP]            EXHIBIT 8.2


                                                 WEBB B. MORROW III
                                                 415 693-2170
                                                 morrowb@cooley.com

BioStar, Inc.
6655 Lookout Road
Boulder, Colorado 80301

Ladies and Gentlemen:

This opinion is being delivered to you in connection with the Form S-4
Registration Statement (the "Registration Statement") filed pursuant to the
Agreement and Plan of Merger and Reorganization dated as of December 22, 1997 
(the "Reorganization Agreement") by and among Cortech, Inc., a Delaware
corporation ("Parent"), Cortech Merger Sub, Inc., a Delaware corporation and
wholly-owned subsidiary of Parent ("Merger Sub"), and BioStar, Inc., a Delaware
corporation (the "Company").

Except as otherwise provided, capitalized terms used but not defined herein
shall have the meanings set forth in the Reorganization Agreement. All section
references, unless otherwise indicated, are to the Internal Revenue Code of
1986, as amended (the "Code").

We have acted as counsel to the Company in connection with the Merger. As such,
and for the purpose of rendering this opinion, we have examined, and are
relying upon (without any independent investigation or review thereof) the
truth and accuracy, at all relevant times, of the statements, covenants,
representations and warranties contained in, the following documents (including
all exhibits and schedules attached thereto):

         (a)     the Reorganization Agreement;

         (b)     those certain tax representation letters delivered to us by
Parent, Merger Sub and the Company containing certain representations of Parent,
Merger Sub and the Company (the "Tax Representation Letters");

         (c)     Continuity of Interest Certificates delivered by certain
stockholders of the Company in favor of Parent, Merger Sub and the Company (the
"Continuity of Interest Certificates"); and

         (d)     such other instruments and documents related to the formation,
organization and operation of Parent, Merger Sub and the Company and related to
the consummation of the Merger and the other transactions contemplated by the
Reorganization Agreement as we have deemed necessary or appropriate.

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         In connection with rendering this opinion, we have assumed (without
         any independent investigation or review thereof) that:

                 1.       Original documents submitted to us (including
         signatures thereto) are authentic, documents submitted to us as copies
         conform to the original documents, and that all such documents have
         been (or will be by the Effective Time) duly and validly executed and
         delivered where due execution and delivery are a prerequisite to the
         effectiveness thereof;

                 2.       All representations, warranties and statements made
         or agreed to by Parent, Merger Sub and the Company, their managements,
         employees, officers, directors and stockholders in connection with the
         Merger, including, but not limited to, those set forth in the
         Reorganization Agreement (including the exhibits thereto), the Tax
         Representation Letters and the Continuity of Interest Certificates are
         true and accurate at all relevant times;

                 3.       All covenants contained in the Reorganization
         Agreement (including exhibits thereto), the Tax Representation Letters
         and the Continuity of Interest Certificates are performed without
         waiver or breach of any material provision thereof;

                 4.       There is no plan or intention on the part of the
         stockholders of the Company to engage in a sale, exchange, transfer,
         distribution, pledge, or other disposition or any transaction which
         results in a reduction of risk of ownership, or a direct or indirect
         disposition of shares of Parent Common Stock to be received in the
         Merger that would reduce the Company's stockholders' ownership of
         Parent Common Stock to a number of shares having an aggregate fair
         market value, as of the Effective Time, of less than fifty percent
         (50%) of the aggregate fair market value of all of the Company capital
         stock outstanding immediately prior to the Effective Time. (For
         purposes of the preceding sentence, shares of Company capital stock
         pursuant to which stockholders of the Company exercise appraisal
         rights in the Merger, which are exchanged for consideration in the
         Merger other than shares of Parent Common Stock, including being
         exchanged for cash in lieu of fractional shares of Parent Common Stock
         or are sold, redeemed or disposed of in a transaction that is in
         contemplation of or related to the Merger, shall be considered shares
         of Company capital stock held by stockholders of the Company
         immediately prior to the Merger which are exchanged for shares of
         Parent Common Stock in the Merger and then disposed of pursuant to a
         plan); and

                 5.       Any representation or statement made "to the best of
         knowledge" or similarly qualified is correct without such
         qualification.



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         April 9, 1998
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         Based on our examination of the foregoing items and subject to the
         limitations, qualifications, assumptions and caveats set forth herein,
         we are of the opinion that, for federal income tax purposes, the
         Merger will be a reorganization within the meaning of Section
         368(a)(1) of the Code.

         In addition to your request for our opinion on this specific matter of
         federal income tax law, you have asked us to review the discussion of
         federal income tax issues contained in the Registration Statement. We
         have reviewed the discussion entitled "Federal Income Tax Consequences"
         contained in the Registration Statement and believe that such
         information fairly presents the current federal income tax law
         applicable to the Merger and the material federal tax consequences to
         Parent, Merger Sub, the Company and the Company's stockholders as a
         result of the Merger.

         We consent to the reference to our firm under the caption "Federal
         Income Tax Consequences" in the Proxy Statement included in the
         Registration Statement and to the filing of this opinion as an exhibit
         to the Proxy Statement and to the Registration Statement.

         This opinion does not address the various state, local or foreign tax
         consequences that may result from the Merger or the other transactions
         contemplated by the Reorganization Agreement. In addition, no opinion
         is expressed as to any federal income tax consequence of the Merger or
         the other transactions contemplated by the Reorganization Agreement
         except as specifically set forth herein, and this opinion may not be
         relied upon except with respect to the consequences specifically
         discussed herein. Furthermore, this opinion only relates to the
         holders of Company capital stock who hold such stock as a capital
         asset. No opinion is expressed as to the federal income tax treatment
         that may be relevant to a particular investor in light of personal
         circumstances or to certain types of investors subject to special
         treatment under the federal income tax laws (for example, life
         insurance companies, dealers in securities, taxpayers subject to the
         alternative minimum tax, banks, tax-exempt organizations, non-United
         States persons, and stockholders who acquired their shares of Company
         capital stock pursuant to the exercise of options or otherwise as
         compensation or who hold their Company capital stock as part of a
         straddle or risk reduction transaction). Further, no opinion is
         expressed as to the federal income tax treatment with respect to
         holders of warrants for Company capital stock.

         No opinion is expressed as to any transaction other than the Merger as
         described in the Reorganization Agreement, or as to any other
         transaction whatsoever, including the Merger, if all of the
         transactions described in the Reorganization Agreement are not
         consummated in accordance with the terms of the Reorganization
         Agreement and without waiver of any material provision thereof. To the
         extent that any of the representations, warranties, statements and
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         assumptions material to our opinion and upon which we have relied are
         not accurate and complete in all material respects at all relevant
         times, our opinion would be adversely affected and should not be
         relied upon.

         This opinion only represents our best judgment as to the federal
         income tax consequences of the Merger and is not binding on the
         Internal Revenue Service or any court of law, tribunal, administrative
         agency or other governmental body. The conclusions are based on the
         Code, existing judicial decisions, administration regulations and
         published rulings. No assurance can be given that future legislative,
         judicial or administrative changes or interpretations would not
         adversely affect the accuracy of the conclusions stated herein.
         Nevertheless, by rendering this opinion, we undertake no 
         responsibility to advise you of any new developments in the 
         application or interpretation of the federal income tax laws.

         This opinion is being delivered in connection with the Registration
         Statement. It is intended for the benefit of Parent, Merger Sub, the
         Company and its stockholders and may not be relied upon or utilized
         for any other purpose or by any other person and may not be made
         available to any other person without our prior written consent.

         Sincerely,

         COOLEY GODWARD LLP

         /s/ Webb B. Morrow III
       
         Webb B. Morrow III

         WBM/dp