EXHIBIT 10.63


THIS WARRANT AND THE  SECURITIES  ISSUABLE  UPON  EXERCISE  HEREOF HAVE NOT BEEN
REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY APPLICABLE STATE
LAWS,  AND NO INTEREST  THEREIN  MAY BE SOLD,  DISTRIBUTED,  ASSIGNED,  OFFERED,
PLEDGED OR  OTHERWISE  TRANSFERRED  UNLESS  THERE IS AN  EFFECTIVE  REGISTRATION
STATEMENT UNDER SUCH ACT AND APPLICABLE  STATE SECURITIES LAWS COVERING ANY SUCH
TRANSACTION OR SUCH TRANSACTION IS EXEMPT FROM THE REGISTRATION  REQUIREMENTS OF
SUCH ACT AND LAWS,  SUCH  COMPLIANCE,  AT THE OPTION OF THE  CORPORATION,  TO BE
EVIDENCED BY AN OPINION OF  WARRANTHOLDER'S  COUNSEL,  IN FORM ACCEPTABLE TO THE
CORPORATION, THAT NO VIOLATION OF SUCH REGISTRATION PROVISIONS WOULD RESULT FROM
ANY PROPOSED TRANSFER OR ASSIGNMENT.


                  SERIES "O" COMMON STOCK PURCHASE WARRANT

                     Bioject Medical Technologies Inc.


THIS CERTIFIES that for good and valuable  consideration  received,  Petkevich &
Partners LLC, a limited liability company,  or registered  assigns, is entitled,
upon the terms and subject to the conditions  hereinafter  set forth, to acquire
from  Bioject   Medical   Technologies   Inc.,   an  Oregon   corporation   (the
"Corporation") up to 80,000 fully paid and nonassessable shares of common stock,
without par value, of the Corporation  ("Warrant Stock") at a purchase price per
share (the "Exercise Price") of $0.625.

1. Term of Warrant

Subject to the terms and  conditions  set forth  herein,  this Warrant  shall be
exercisable,  in whole or from  time to time  part,  at any time on or after the
date hereof and at or prior to 11:59 p.m.,  Pacific  Standard  Time,  on May 10,
2004 (the "Expiration Time").

2. Exercise of Warrant

The  purchase  rights  represented  by  this  Warrant  are  exercisable  by  the
registered holder hereof, in whole or in part, at any time and from time to time
at or prior to the  Expiration  Time by the  surrender  of this  Warrant and the
Notice of  Exercise  form  attached  hereto  duly  executed to the office of the
Corporation at 7620 S.W. Bridgeport Road, Portland,  Oregon 97224 (or such other
office or agency of the  Corporation as it may designate by notice in writing to
the  registered  holder  hereof at the address of such holder  appearing  on the
books of the Corporation), and upon payment of the Exercise Price for the shares
thereby purchased (by cash or by check or bank draft payable to the order of the
Corporation or by  cancellation of indebtedness of the Corporation to the holder
hereof, if any, at the time of exercise in an amount equal to the purchase price
of the shares thereby purchased);  whereupon the holder of this Warrant shall be
entitled to receive  from the  Corporation  a stock  certificate  in proper form
representing the number of shares of Warrant Stock so purchased.

3. Issuance of Shares; No Fractional Shares of Scrip

Certificates  for shares  purchased  hereunder  shall be delivered to the holder
hereof by the Corporation's transfer agent at the Corporation's expense within a
reasonable  time after the date on which this Warrant shall have been  exercised
in accordance with the terms hereof.  Each  certificate so delivered shall be in
such  denominations  as may be  requested  by the  holder  hereof  and  shall be
registered in the name of such holder or, subject to applicable laws, other name
as shall be requested by such holder.  If, upon exercise of this Warrant,  fewer


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than all of the shares of Warrant Stock  evidenced by this Warrant are purchased
prior to the Expiration Time, one or more new warrants substantially in the form
of, and on the terms in, this Warrant will be issued for the remaining number of
shares of  Warrant  Stock not  purchased  upon  exercise  of this  Warrant.  The
Corporation  hereby  represents  and warrants  that all shares of Warrant  Stock
which may be issued upon the exercise of this Warrant will,  upon such exercise,
be duly and validly authorized and issued, fully paid and nonassessable and free
from all taxes, liens and charges in respect of the issuance thereof (other than
liens or charges  created by or imposed  upon the holder of the Warrant  Stock).
The  Corporation  agrees that the shares so issued  shall be and be deemed to be
issued to such  holder  as the  record  owner of such  shares as of the close of
business  on the date on which  this  Warrant  shall have been  surrendered  for
exercise in  accordance  with the terms hereof.  No  fractional  shares or scrip
representing  fractional  shares  shall  be  issued  upon the  exercise  of this
Warrant. With respect to any fraction of a share called for upon the exercise of
this Warrant,  an amount equal to such  fraction  multiplied by the then current
price at which each share may be  purchased  hereunder  shall be paid in cash to
the holder of this Warrant.

4. Charges, Taxes and Expenses

Issuance of  certificates  for shares of Warrant Stock upon the exercise of this
Warrant  shall be made  without  charge to the  holder  hereof  for any issue or
transfer  tax or other  incidental  expense in respect of the  issuance  of such
certificate,  all of which taxes and expenses shall be paid by the  Corporation,
and such certificates  shall be issued in the name of the holder of this Warrant
or in such  name or names as may be  directed  by the  holder  of this  Warrant;
provided,  however,  that in the event  certificates for shares of Warrant Stock
are to be issued in a name other  than the name of the  holder of this  Warrant,
this  Warrant  when  surrendered  for  exercise  shall  be  accompanied  by  the
Assignment Form attached hereto duly executed by the holder hereof.

5. No Rights as Shareholders

This  Warrant does not entitle the holder  hereof to any voting  rights or other
rights as a shareholder of the Corporation prior to the exercise hereof.

6. Registration Rights

This  Warrant is a Series "O"  Warrant  identified  in the  Registration  Rights
Agreement  dated as of May 10,  1999,  between the  Corporation  and the parties
listed on the signature pages thereto. A transferee of this Warrant may become a
"Holder" as defined in such agreement upon compliance  with the  requirements of
such agreement.

7. Exchange and Registry of Warrant

This Warrant is exchangeable, upon the surrender hereof by the registered holder
at the above-mentioned office or agency of the Corporation, for a new Warrant of
like tenor and dated as of such exchange.  The Corporation shall maintain at the
above-mentioned  office or agency a registry showing the name and address of the
registered holder of this Warrant. This Warrant may be surrendered for exchange,
transfer or exercise,  in accordance with its terms, at such office or agency of
the Corporation,  and the Corporation shall be entitled to rely in all respects,
prior to written notice to the contrary, upon such registry.

8. Loss, Theft, Destruction or Mutilation of Warrant

Upon receipt by the Corporation of evidence reasonably satisfactory to it of the
loss,  theft,  destruction  or mutilation of this Warrant,  and in case of loss,
theft or destruction of indemnity or security reasonably satisfactory to it, and
upon  reimbursement  to the  Corporation of all reasonable  expenses  incidental
thereto, and upon surrender and cancellation of this Warrant, if mutilated,  the
Corporation  will make and  deliver a new  Warrant of like tenor and dated as of
such cancellation, in lieu of this Warrant.

9. Saturdays, Sundays and Holidays

If the last or appointed  day for the taking of any action or the  expiration of
any right required or granted herein shall be a Saturday or a Sunday or shall be
a legal holiday, then such action may be taken or such right may be exercised on
the next succeeding day not a Saturday, Sunday or legal holiday.


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10. Merger, Sale of Assets, Etc.

If at any time the Corporation proposes to merge or consolidate with or into any
other  corporation,  effect  any  reorganization,  or  sell  or  convey  all  or
substantially  all of its assets to any other  entity,  then,  as a condition of
such reorganization,  consolidation, merger, sale or conveyance, the Corporation
or its successor,  as the case may be, shall enter into a supplemental agreement
to make lawful and adequate provision whereby the holder shall have the right to
receive,  upon exercise of the Warrant, the kind and amount of equity securities
which would have been received upon such reorganization,  consolidation, merger,
sale or  conveyance  by a holder of a number of shares of common  stock equal to
the number of shares issuable upon exercise of the Warrant  immediately prior to
such reorganization,  consolidation, merger, sale or conveyance. If the property
to  be  received  upon  such  reorganization,  consolidation,  merger,  sale  or
conveyance is not equity  securities,  the Corporation  shall give the holder of
this  Warrant  ten (10)  business  days  prior  written  notice of the  proposed
effective date of such  transaction,  and if this Warrant has not been exercised
by or on the effective date of such transaction, it shall terminate.

11. Subdivision, Combination, Reclassification, Conversion, Etc.

If  the   Corporation   at  any  time  shall,   by   subdivision,   combination,
reclassification  of securities or otherwise,  change the Warrant Stock into the
same or a different  number of securities of any class or classes,  this Warrant
shall  thereafter  entitle  the  holder  to  acquire  such  number  and  kind of
securities as would have been issuable in respect of the Warrant Stock (or other
securities  which  were  subject  to the  purchase  rights  under  this  Warrant
immediately prior to such subdivision,  combination,  reclassification  or other
change) as the result of such change if this Warrant had been  exercised in full
for cash immediately prior to such change. The Exercise Price hereunder shall be
adjusted if and to the extent  necessary to reflect such change.  If the Warrant
Stock or other  securities  issuable  upon  exercise  hereof are  subdivided  or
combined into a greater or smaller number of shares of such security, the number
of shares issuable hereunder shall be proportionately increased or decreased, as
the case may be, and the  Exercise  Price  shall be  proportionately  reduced or
increased,  as the case may be, in both cases  according  to the ratio which the
total number of shares of such security to be outstanding immediately after such
even  bears  to  the  total  number  of  shares  of  such  security  outstanding
immediately  prior to such event.  The Corporation  shall give the holder prompt
written notice of any change in the type of securities issuable  hereunder,  any
adjustment of the Exercise Price for the securities issuable hereunder,  and any
increase or decrease in the number of shares issuable hereunder.

12. Transferability; Compliance with Securities Laws

(a) This Warrant may not be  transferred or assigned in whole or in part without
compliance  with  all  applicable  federal  and  state  securities  laws  by the
transferor and transferee  (including the delivery of investment  representation
letters  and legal  opinions  reasonably  satisfactory  to the  Corporation,  if
requested  by  the  Corporation).   Subject  such  restrictions,  prior  to  the
Expiration  Time, this Warrant and all rights  hereunder are transferable by the
holder hereof,  in whole or in part, at the office or agency of the  Corporation
referred to in Section 1 hereof. Any such transfer shall be made in person or by
the holder's duly authorized  attorney,  upon surrender of this Warrant together
with the Assignment Form attached hereto properly endorsed.

(b) The Holder of this Warrant,  by acceptance  hereof,  acknowledges  that this
Warrant and the Warrant Stock  issuable upon exercise  hereof are being acquired
solely for the  holder's  own account and not as a nominee for any other  party,
and for  investment,  and that the  holder  will not  offer,  sell or  otherwise
dispose  of this  Warrant  or any  shares of  Warrant  Stock to be  issued  upon
exercise hereof except under  circumstances  that will not result in a violation
of the Securities Act of 1933, as amended,  or any state  securities  laws. Upon
exercise of this  Warrant,  the holder shall,  if requested by the  Corporation,
confirm in writing,  in a form satisfactory to the Corporation,  that the shares
of Warrant Stock so purchased are being acquired solely for holder's own account
and not as a nominee for any other party,  for  investment,  and not with a view
toward distribution or resale.


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(c) The  Warrant  Stock  has not  been  and will  not be  registered  under  the
Securities Act of 1933, as amended, and this Warrant may not be exercised except
by (i) the original  purchaser of this Warrant from the  Corporation  or (ii) an
"accredited  investor"  as defined in Rule 501(a)  under the  Securities  Act of
1933,  as amended.  Each  certificate  representing  the Warrant  Stock or other
securities  issued in respect of the Warrant  Stock upon any stock split,  stock
dividend,  recapitalization,  merger,  consolidation or similar event,  shall be
stamped or otherwise imprinted with a legend substantially in the following form
(in addition to any legend required under applicable securities laws):

THE SECURITIES  REPRESENTED  HEREBY HAVE NOT BEEN REGISTERED UNDER UNITED STATES
FEDERAL  OR STATE  SECURITIES  LAWS AND MAY NOT BE  OFFERED  FOR  SALE,  SOLD OR
OTHERWISE TRANSFERRED OR ASSIGNED FOR VALUE, DIRECTLY OR INDIRECTLY, NOR MAY THE
SECURITIES BE TRANSFERRED ON THE BOOKS OF THE CORPORATION,  WITHOUT REGISTRATION
OF  SUCH  SECURITIES  UNDER  ALL  APPLICABLE  UNITED  STATES  FEDERAL  OR  STATE
SECURITIES  LAWS OR COMPLIANCE  WITH AN  APPLICABLE  EXEMPTION  THEREFROM,  SUCH
COMPLIANCE,  AT THE OPTION OF THE CORPORATION,  TO BE EVIDENCED BY AN OPINION OF
SHAREHOLDER'S COUNSEL, IN FORM ACCEPTABLE TO THE CORPORATION,  THAT NO VIOLATION
OF SUCH  REGISTRATION  PROVISIONS  WOULD  RESULT FROM ANY  PROPOSED  TRANSFER OR
ASSIGNMENT.

13. Representations and Warranties

The Corporation hereby represents and warrants to the holder hereof that:

(a) during the period this Warrant is outstanding,  the Corporation will reserve
from its authorized and unissued  common stock a sufficient  number of shares to
provide for the issuance of Warrant Stock upon the exercise of this Warrant;

(b)  the  issuance  of this  Warrant  shall  constitute  full  authority  to the
Corporation's  officers  who  are  charged  with  the  duty of  executing  stock
certificates to execute and issue the necessary  certificates  for the shares of
Warrant Stock issuable upon exercise of this Warrant;

(c) the  Corporation  has all requisite legal and corporate power to execute and
deliver this Warrant,  to sell and issue the Warrant Stock  hereunder,  to issue
the common stock  issuable  upon  exercise of the Warrant Stock and to carry out
and perform its obligations under the terms of this Warrant;

(d) all  corporate  action on the part of the  Corporation,  its  directors  and
shareholders   necessary  for  the   authorization,   execution,   delivery  and
performance  of  this  Warrant  by the  Corporation,  the  authorization,  sale,
issuance and delivery of the Warrant Stock, the grant of registration  rights as
provided herein and the performance of the Corporation's  obligations  hereunder
has been taken;

(e) the Warrant  Stock,  when issued in compliance  with the  provisions of this
Warrant and the Corporation's  Articles of Incorporation (as they may be amended
from time to time (the  "Articles")),  will be  validly  issued,  fully paid and
nonassessable,  and free of all taxes, liens or encumbrances with respect to the
issue thereof,  and will be issued in compliance with all applicable federal and
state securities laws; and

(f) the  issuance  of the  Warrant  Stock will not be subject to any  preemptive
rights, rights of first refusal or similar rights.


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14. Corporation

The  Corporation  will  not,  by  amendment  of  its  Articles  or  through  any
reorganization,  recapitalization,  transfer of assets,  consolidation,  merger,
dissolution,  issue or sale of securities or any other action,  avoid or seek to
avoid  the  observance  or  performance  of any of the terms to be  observed  or
performed  hereunder  by the  Corporation,  but will at all times in good  faith
assist in the  carrying  out of all the  provisions  of this  Warrant and in the
taking of all such action as may be necessary or appropriate in order to protect
the rights of the holder of the Warrant against impairment.

15. Governing Law

This Warrant shall be governed by and  construed in accordance  with the laws of
the State of Oregon.


IN WITNESS  WHEREOF,  the  Corporation has caused this Warrant to be executed by
its duly authorized officers.

Dated: May 10, 1999


BIOJECT MEDICAL TECHNOLOGIES INC.


By: ----------------------------

Name: Michael Temple
Title: Vice President, Chief Financial Officer & Secretary


                                  NOTICE OF EXERCISE

To: Bioject Medical Technologies Inc.

(1) The undersigned hereby elects to purchase -------- shares of common stock of
Bioject Medical Technologies Inc. pursuant to the terms of the attached Warrant,
and tenders  herewith  payment of the purchase price in full,  together with all
applicable transfer taxes, if any.

(2) In exercising this Warrant, the undersigned hereby confirms and acknowledges
that the  shares of common  stock to be issued  upon  exercise  hereof are being
acquired  solely for the account of the undersigned and not as a nominee for any
other party, and for investment,  and that the undersigned will not offer,  sell
or  otherwise   dispose  of  any  such  shares  of  common  stock  except  under
circumstances that will not result in a violation of the Securities Act of 1933,
as amended, or any state securities laws.

(3) Please  issue a  certificate  or  certificates  representing  said shares of
common  stock  in the  name  of the  undersigned  or in  such  other  name as is
specified below:


                            ------------------------------
                                        (Name)

                            ------------------------------
                                       (Address)



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(3) The undersigned  represents that (a) he, she or it is the original purchaser
from the Corporation of the attached Warrant or an "accredited  investor" within
the meaning of Rule 501(a) under the  Securities Act of 1933, as amended and (b)
the aforesaid  shares of common stock are being  acquired for the account of the
undersigned  for  investment and not with a view to, or for resale in connection
with, the distribution thereof and that the undersigned has no present intention
of distributing or reselling such shares.

- --------------                       ----------------------------------
(Date)                                  (Signature)


                             ASSIGNMENT FORM

(To  assign  the  foregoing  Warrant,  execute  this  form and  supply  required
information. Do not use this form to purchase shares.)



FOR VALUE  RECEIVED,  the  undersigned  registered  owner of this Warrant hereby
sells,  assigns and transfers unto the Assignee named below all of the rights of
the undersigned  under the within Warrant,  with respect to the number of shares
of common stock of Bioject Medical Technologies Inc. set forth below:

Name of Assignee             Address               No. of Shares
- ----------------             -------               -------------



and does hereby irrevocably  constitute and appoint Attorney ---------------- to
make such transfer on the books of Bioject Medical Technologies Inc., maintained
for the purpose, with full power of substitution in the premises.

The  undersigned  also  represents  that,  by  assignment  hereof,  the Assignee
acknowledges  that  this  Warrant  and the  shares  of stock to be  issued  upon
exercise hereof are being acquired for investment and that the Assignee will not
offer,  sell or  otherwise  dispose of this Warrant or any shares of stock to be
issued upon exercise hereof except under  circumstances which will not result in
a violation of the Securities Act of 1933, as amended,  or any state  securities
laws. Further,  the Assignee shall, if requested by the Corporation,  confirm in
writing, in a form satisfactory to the Corporation,  that the shares of stock so
purchased  are  being  acquired  for  investment  and  not  with a  view  toward
distribution or resale.



                                    Dated:------------------------------

                                    Holder's Signature:-----------------

                                    Holder's Address:
                                    ------------------------------------

                                    ------------------------------------


Guaranteed Signature:

NOTE: The signature to this  Assignment Form must correspond with the name as it
appears on the face of the Warrant,  without  alteration or  enlargement  or any
change whatever, and must be guaranteed by a bank or trust company.  Officers of
corporations  and those action in a fiduciary or other  representative  capacity
should file proper evidence of authority to assign the foregoing Warrant.


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