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                                                                     EXHIBIT 8.2

                        [Letterhead of Perkins Coie LLP]


                                 April 25, 2003


Ostex International, Inc.
2203 Airport Way, South, Suite 400
Seattle, WA  98134


       RE:  ACQUISITION BY INVERNESS MEDICAL INNOVATIONS, INC.

Ladies and Gentlemen:

       This opinion is being delivered to you in accordance with Section 7.2(e)
of the Agreement and Plan of Merger dated as of September 6, 2002, as amended on
February 18, 2003 (the "Merger Agreement"), by and among Inverness Medical
Innovations, Inc., a Delaware corporation ("Inverness"), Geras Acquisition
Corp., a Washington corporation and a wholly owned subsidiary of Inverness
("MergerCo"), and Ostex International, Inc., a Washington corporation ("Ostex").
Unless otherwise indicated, capitalized terms used herein have the meaning
ascribed to them in the Merger Agreement.

       In delivering this opinion, we have examined and relied upon originals or
copies, certified or otherwise identified to our satisfaction, of (i) the Merger
Agreement, (ii) Amendment No. 1 to the Registration Statement on Form S-4 filed
with the United States Securities and Exchange Commission (the "Commission")
under the Securities Act of 1933, as amended (the "Securities Act"), on April
25, 2003 (the "Registration Statement"), which Registration Statement includes
the Proxy Statement/Prospectus, and (iii) such other documents, certificates and
records as we have deemed necessary or appropriate. In addition, we have relied
upon, and assumed as true, correct, and complete at all relevant times, without
any independent investigation, (i) the statements, covenants, representations
and warranties contained in the Merger Agreement (including all schedules and
exhibits thereto); and (ii) the statements contained in the Registration
Statement and the representation letters

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Ostex International, Inc.
April 25, 2003
Page 2


delivered to us by Inverness, MergerCo, and Ostex pursuant to the Merger
Agreement (the "Tax Representation Letters").

       We have also assumed, without any independent investigation, (i) the
authenticity of original documents submitted to us, the conformity to the
originals of documents submitted to us as copies, and the due and valid
execution and delivery of all such documents where due execution and delivery
are a prerequisite to the effectiveness thereof; (ii) the performance of all
covenants contained in the Merger Agreement and the Tax Representation Letters
without waiver or breach of any material provision thereof; and (iii) the
accuracy of any representation or statement "to the best knowledge" or similarly
qualified without such qualification.

       Based upon the foregoing, and subject to the limitations, qualifications,
assumptions and caveats set forth herein, we are of the opinion that the Merger
will qualify as a reorganization within the meaning of Section 368(a) of the
Internal Revenue Code of 1986, as amended (the "Code").

       Furthermore, based upon the foregoing and subject to the limitations and
qualifications set forth herein, we are of the opinion that under current United
States federal income tax law, the discussion set forth in the Registration
Statement under the heading "Material Federal Income Tax Consequences," to the
extent it describes legal matters or legal conclusions, is accurate in all
material respects.

       Our opinion herein is based on, as of the date hereof, the applicable
provisions of the Code, Treasury Regulations promulgated or proposed thereunder,
current positions of the Internal Revenue Service contained in published revenue
rulings, revenue procedures and announcements, pertinent judicial authorities
and other applicable authorities, all of which are subject to change either
prospectively or retroactively. No assurance can be given that future
legislative, judicial or administrative changes, on either a prospective or
retroactive basis, would not adversely affect the accuracy of our opinion.

       This opinion is expressed as of the date hereof, and we undertake no
responsibility to advise you of any subsequent changes of the facts stated or
assumed herein, or of any new developments in the application or interpretation
of the federal income tax laws. In the event any one of the statements,
representations, warranties or assumptions upon which we have relied to issue
this opinion is incorrect, our opinion might be adversely affected and may not
be relied upon. This opinion

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Ostex International, Inc.
April 25, 2003
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addresses only the matters described above, and does not address any other
federal state, local or foreign tax consequences that may result from the
Merger.

       We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the use of our name under the captions "LEGAL
MATTERS" and "Material Federal Income Tax Consequences" in the Registration
Statement. In giving this consent, we do not thereby admit that we are in the
category of persons whose consent is required under Section 7 of the Securities
Act, nor do we admit that we are experts with respect to any part of the
Registration Statement within the meaning of the term "expert" as used in the
Securities Act.

                                         Very truly yours,

                                         /s/ PERKINS COIE LLP

                                         PERKINS COIE LLP