Exhibit 4.7

                    CERTIFICATE OF DESIGNATIONS, PREFERENCES

                       AND RIGHTS OF SERIES A CONVERTIBLE

                                 PREFERRED STOCK

                                       OF

                          IMCLONE SYSTEMS INCORPORATED

      IMCLONE SYSTEMS INCORPORATED (the "Company"),  a corporation organized and
existing under the General Corporation Law of the State of Delaware, does hereby
certify that, pursuant to authority conferred upon the Board of Directors of the
Company by the  Certificate  of  Incorporation,  as amended,  of the Company and
pursuant to Section 151 of the General Corporation Law of the State of Delaware,
the Board of  Directors  of the  Company at a meeting  duly held on  December 3,
1997,  adopted  resolutions  providing  for the  designations,  preferences  and
relative,  participating,  optional  or other  rights,  and the  qualifications,
limitations or restrictions  thereof,  of four hundred thousand (400,000) shares
of Series A Convertible Preferred Stock (the "Series A Preferred Shares") of the
Company, as follows:

      RESOLVED,  that the  Company is  authorized  to issue  400,000  Tshares of
Series A Convertible  Preferred  Stock (the "Series A Preferred  Shares")  which
shall have the following  powers,  designations,  preferences  and other special
rights:

      (1)  Dividends.  The  holders of the then  outstanding  Series A Preferred
Shares shall be entitled to receive,  out of funds legally  available  therefor,
cumulative  dividends  at the  annual  rate of 6% of the  Stated  Value  thereof
compounded  annually  (pro-rated for any portion of the applicable period during
which such  Series A  Preferred  Shares  are  outstanding).  Dividends  shall be
payable on the Series A Preferred  Shares then  outstanding in cash (i) annually
on December 31st of each year beginning on December 31, 1999 or (ii) at the time
of  conversion  or  redemption  (as  provided  herein) of the Series A Preferred
Shares on which the dividend is to be paid, whichever is


                                       1


sooner.  Dividends on the Series A Preferred  Shares shall accumulate and accrue
from the date of original  issuance and shall accrue from day to day thereafter,
whether or not earned or declared.  Until any such  dividend in arrears is paid,
dividends  shall  continue to accrue on each  Series A  Preferred  Share but the
percentage  rate  expressed  herein shall be applied to the Stated Value thereof
plus all  dividends  thereon  (including  dividends  computed  pursuant  to this
sentence).

      (2) Conversion of Series A Preferred  Shares.  The holders of the Series A
Preferred Shares shall have the right, at their option,  to convert the Series A
Preferred  Shares  into  shares  of  Common  Stock on the  following  terms  and
conditions:

            (a) Each Series A Preferred  Share shall be  convertible at any time
      as  hereinafter  provided (or, if such Series A Preferred  Share is called
      for redemption,  at any time up to and including, but not after, the close
      of  business  on the fifth full  business  day prior to the date fixed for
      such redemption,  unless default shall be made by the Company in providing
      the funds for the payment of the  redemption  price),  into fully paid and
      nonassessable  shares  (calculated  to the nearest  whole share) of Common
      Stock of the Company as constituted at the time of such conversion, at the
      conversion  price  in  effect  at the  time of  conversion  determined  as
      hereinafter  provided (the  "Conversion  Price").  Each Series A Preferred
      Share  shall have a value of $100 (the  "Stated  Value") and the number of
      shares of Common Stock  issuable  upon  conversion of each of the Series A
      Preferred  Shares shall be determined by dividing the Stated Value thereof
      by the  Conversion  Price then in effect.  Every  reference  herein to the
      Common Stock of the Company  (unless a different  intention is  expressed)
      shall be to the  shares  of the  Common  Stock of the  Company,  $.001 par
      value, as such stock exists immediately after the issuance of the Series A
      Preferred  Shares  provided  for  hereunder,  or to stock  into which such
      Common Stock may be changed from time to time thereafter.

            (b) The Series A Preferred  Shares  shall be  convertible  as of the
      dates set forth in (i) - (iv) below.

                  (i) up to 100,000  Series A  Preferred  Shares  ("Tranche  I")
            shall be  convertible  at any time on or after the date on which the
            Series A Preferred Shares are issued (the "Issuance Date");  (ii) up
            to an additional  100,000 Series A Preferred  Shares  ("Tranche II")
            shall be  convertible  at any time on or after  January 1, 2000 (the
            "Second Anniversary Date"); (iii) up to an additional 100,000 Series
            A Preferred  Shares ("Tranche III") shall be convertible at any time
            on or after January 1, 2001 (the "Third Anniversary Date"); and (iv)
            up to an additional 100,000 Series A Preferred Shares ("Tranche IV")
            shall be  convertible  at any time on or after  January 1, 2002 (the
            "Fourth Anniversary Date").

            (c) The  Series  A  Preferred  Shares  shall be  convertible  at the
      Conversion Prices set forth in (i) - (v) below.


                                       2


                  (i)  Series A  Preferred  Shares  converted  on or  after  the
            Issuance  Date and  before  the  Second  Anniversary  Date  shall be
            convertible at a per share  Conversion  Price equal to $12.50;  (ii)
            Series  A  Preferred   Shares  converted  on  or  after  the  Second
            Anniversary  Date and  before  the Third  Anniversary  Date shall be
            convertible  at a per share  Conversion  Price  equal to 100% of the
            Average  Market Price (as defined below) of the Common Stock for the
            five (5)  consecutive  trading  days ending one trading day prior to
            the  Second  Anniversary  Date;  (iii)  Series  A  Preferred  Shares
            converted  on or after the Third  Anniversary  Date and  before  the
            Fourth  Anniversary  Date  shall  be  convertible  at  a  per  share
            Conversion  Price  equal to 100% of the  Average  Market  Price  (as
            defined  below) of the  Common  Stock  for the five (5)  consecutive
            trading  days ending one trading day prior to the Third  Anniversary
            Date;  (iv)  Series A  Preferred  Shares  converted  on or after the
            Fourth  Anniversary  Date  and  before  January  1,  2003  shall  be
            convertible  at a per  share  Conversion  Price  equal to 88% of the
            Average  Market Price (as defined below) of the Common Stock for the
            five (5)  consecutive  trading  days ending one trading day prior to
            the  Fourth  Anniversary  Date;  and (v) Series A  Preferred  Shares
            converted on or after January 1, 2003 shall be  convertible at a per
            share Conversion Price equal to 100% of the Average Market Price (as
            defined  below) of the  Common  Stock  for the five (5)  consecutive
            trading  days ending one (1) trading day prior to the receipt by the
            Company of the Conversion Notice (as defined below).

            (d)  Notwithstanding  anything to the contrary  contained herein, in
      the  event (i) the  Conversion  Price in  effect  from time to time  under
      Section 2(c) is less than the Average  Market Price (as defined  below) of
      the Common  Stock for the five (5)  consecutive  trading  days  ending one
      trading day prior to the Issuance  Date,  and (ii) the number of shares of
      Common  Stock that would be issued at such  Conversion  Price would exceed
      that  number  of  shares of  Common  Stock  permitted  to be issued by the
      Company  without  shareholder  approval  under the  rules of the  National
      Association of Securities  Dealers  Automated  Quotation System ("NASDAQ")
      (the "Permissible  Shares"),  then the Company shall issue the Permissible
      Shares as herein provided,  and with respect to those shares exceeding the
      Permissible  Shares  (the  "Excess  Shares")  the  Company  shall  use its
      reasonable best efforts to take such action as will permit it to issue the
      Excess  Shares,  and if the  Company  is unable to  obtain  such  required
      permission   within  a  reasonable  period  of  time,  the  Company  shall
      repurchase  the Excess Shares at a per share  purchase  price equal to the
      Stated Value, plus accrued and unpaid dividends thereon.

            (e)  Notwithstanding  anything  to the  contrary  contained  herein,
      should the Average Market Price (as defined below) of the Common Stock for
      the five (5) consecutive  trading days ending one trading day prior to any
      trading  day  during  which  any of the  Series  A  Preferred  Shares  are
      outstanding  exceed 150% of the Conversion  Price then in effect,  then so
      long as such price is in excess of such  percentage  the  Company,  in its
      sole discretion,  may require the holder of such Series A Preferred Shares
      to convert all such Series A Preferred Shares as may then be convertible.


                                       3


            (f) "Average  Market  Price" of any security for any period shall be
      computed as the arithmetic average of the closing prices for such security
      for each trading day in such period on the NASDAQ National Market,  or, if
      the NASDAQ  National  Market is not the principal  trading market for such
      security, on the principal trading market for such security, or, if market
      value cannot be calculated for such period on any of the foregoing  bases,
      the average fair market value during such period as reasonably  determined
      in good faith by the Board of Directors of the Company.

            (g) The Conversion  Price shall be subject to adjustments  from time
      to time as follows:

                  (i) If and whenever on or after the Issuance  Date the Company
            issues,  sells or exchanges  other than in an Excluded  Issuance (as
            hereinafter defined),  any share of Common Stock for a consideration
            per share less than the Average Market Price of the Common Stock for
            the five (5)  consecutive  trading days ending one trading day prior
            to such  event  (the  "Actual  Price") (a  "Dilutive  Event"),  then
            forthwith  upon such  issue or sale the  Conversion  Price  shall be
            decreased by multiplying the Conversion Price in effect  immediately
            before the Dilutive  Event by a fraction,  the numerator of which is
            the  number of shares of Common  Stock  that are  Outstanding  on an
            As-Converted   Basis  (as  defined  below)  immediately  before  the
            Dilutive  Event plus the number of shares of Common Stock that could
            be purchased  at the Actual Price at the time of the Dilutive  Event
            for the  aggregate  consideration  paid or payable  upon the sale or
            issuance of Common Stock in the Dilutive Event,  and the denominator
            of  which  is  the  number  of  shares  of  Common  Stock  that  are
            Outstanding on an As-Converted Basis immediately before the Dilutive
            Event plus the number of shares that are  acquired or to be acquired
            upon the sale or issuance of the Common Stock in the Dilutive Event.
            For purposes of this paragraph (1),  "Outstanding on an As-Converted
            Basis  immediately  before the Dilutive  Event" means the sum of (i)
            all Common  Stock  issued  and  outstanding  immediately  before the
            Dilutive Event plus (ii) all Common Stock issuable upon the exercise
            of options or  warrants  or  conversion  of  convertible  securities
            outstanding immediately before the Dilutive Event.

                  (ii) "Excluded Issuance" means the issue or sale of (i) shares
            of Common  Stock by the Company  pursuant to the exercise of options
            and warrants outstanding  immediately prior to the Issuance Date (as
            adjusted  pursuant to the terms of such securities to give effect to
            stock  dividends  or stock  splits  or a  combination  of  shares in
            connection with a recapitalization,  merger,  consolidation or other
            reorganization  occurring after the Issuance Date),  (ii) options to
            acquire  Common Stock pursuant to a resolution of, or a stock option
            plan  approved by a  resolution  of, the Board of  Directors  of the
            Company (or the  compensation  committee or stock  option  committee
            thereof)  to  the  Company's  employees,   directors  or  Scientific


                                       4


            Advisory  Board  members,  or (iii) shares of Common Stock issued by
            the Company as  dividends  on, or upon  conversion  of, the Series A
            Preferred Shares.

                  (iii) If after the  Issuance  Date the  Company  in any manner
            grants or issues any option, warrant or convertible security and the
            price per share for which shares of Common  Stock are issuable  upon
            the exercise of any such option,  warrant or convertible security is
            less than the  Actual  Price  with  respect to such date of grant or
            issuance,  then such shares of Common  Stock shall be deemed to have
            been issued and sold by the  Company at the time of the  granting or
            issuance of such option,  warrant or  convertible  security for such
            price  per share  and the  Conversion  Price  shall be  adjusted  in
            accordance with paragraph (i) above. For purposes of this paragraph,
            the "price per share" for which  shares of Common Stock are issuable
            upon  the   conversion  or  exercise  of  any  option,   warrant  or
            convertible  security  shall be equal to the sum of the  amounts  of
            consideration  (if any)  received or  receivable by the Company with
            respect to such shares of Common Stock upon the granting or issuance
            of the option,  warrant or convertible security and upon exercise or
            conversion  of the  option,  warrant  or  convertible  security.  No
            further  adjustment of the  Conversion  Price shall be made upon the
            actual issue of such Common Stock upon the exercise or conversion of
            such option, warrant or convertible security.

                  (iv) If after the Issuance  Date the purchase  price  provided
            for in any option or warrant, the additional  consideration (if any)
            payable upon the issue,  conversion  or exchange of any  convertible
            security,   or  the  rate  at  which  any  convertible  security  is
            convertible  into or  exchangeable  for Common Stock  changes at any
            time, any Conversion Price previously  adjusted with respect to such
            option, warrant or convertible security and in effect at the time of
            such change shall be readjusted to the Conversion  Price which would
            have  been in  effect  at such  time had  such  option,  warrant  or
            convertible  security  originally provided for such changed purchase
            price,  additional  consideration or changed conversion rate, as the
            case may be, at the time initially granted, issued or sold.

                  (v)  Upon the  expiration  of any  option  or  warrant  or the
            termination of any right to convert any convertible security,  after
            the  Issuance  Date,  without  the  exercise  of any such  option or
            warrant,  any  Conversion  Price then in effect  hereunder  shall be
            adjusted to the Conversion  Price which would have been in effect at
            the time of such expiration or termination had such option,  warrant
            or convertible security, to the extent outstanding immediately prior
            to such expiration or termination, never been issued.

                  (vi) In case any  option or  warrant  is issued in  connection
            with the issue or sale of other securities of the Company,  together
            comprising  one (1)  integrated  transaction  in which  no  specific
            consideration  is allocated to such option


                                       5


            or warrant by the parties  thereto,  the option or warrant  shall be
            deemed to have been issued for a consideration of $.0l.

                  (vii) If the Company shall  consolidate with or merge into any
            corporation  or reclassify  its  outstanding  shares of Common Stock
            (other than by way of subdivision or reduction of such shares) (each
            a "Major  Transaction"),  then each Series A  Preferred  Share shall
            thereafter  be  convertible  into the  number  of shares of stock or
            securities (the "Resulting  Securities") or property of the Company,
            or of the entity  resulting from such  consolidation  or merger,  to
            which a holder of the  number of  shares of Common  Stock  delivered
            upon  conversion  of such Series A  Preferred  Share would have been
            entitled upon such Major Transaction had the holder of such Series A
            Preferred  Share  exercised  its  right of  conversion  and had such
            Common  Stock been issued and  outstanding  and had such holder been
            the holder of record of such Common  Stock at the time of such Major
            Transaction, and the Company shall make lawful provision therefor as
            a part of such consolidation, merger or reclassification.

                  (viii) If at any time, or from time to time after the Issuance
            Date,  the  Company  shall (i) declare and pay, on or in respect of,
            its Common Stock any  dividend  payable in shares of Common Stock or
            (ii) subdivide the outstanding shares of Common Stock into a greater
            number of  shares,  or reduce  the  number of  outstanding  Series A
            Preferred  Shares by combining such Series A Preferred Shares into a
            smaller number of Series A Preferred Shares, the Conversion Price in
            effect at the time of the  taking of a record for such  dividend  or
            the taking of such other action shall be  proportionately  decreased
            as of such time, and  conversely  (iii) if at any time, or from time
            to time, the Company shall reduce the number of  outstanding  shares
            of Common  Stock by combining  such shares into a smaller  number of
            shares, or subdivide the outstanding  Series A Preferred Shares into
            a greater number of Series A Preferred Shares,  the Conversion Price
            in effect  at the time of the  taking  of any such  action  shall be
            proportionately increased as of such time.

                  (ix)   Anything   in   this   Section   2  to   the   contrary
            notwithstanding, the Company shall not be required to give effect to
            any  adjustment  in the  Conversion  Price  unless and until the net
            effect of one or more  adjustments,  determined  as above  provided,
            shall have resulted in a change of the Conversion  Price by at least
            $0.05,  provided,  however,  that when the  cumulative net effect of
            more  than one  adjustment  so  determined  shall be to  change  the
            Conversion  Price by at least  $0.05 such  change in the  Conversion
            Price shall thereupon be given effect.

                  (x) The  Company  shall not issue any  fraction  of a share of
            Common Stock upon any conversion,  but shall pay in cash therefor at
            the Conversion Price then in effect multiplied by such fraction.


                                       6


                  (xi) Notice of  Adjustments of Conversion  Rate.  Whenever the
            Conversion Price is adjusted as provided  herein,  the Company shall
            promptly (and, in any event, not later than the fifteenth (15th) day
            following the  occurrence of the event  requiring  such  adjustment)
            compute the adjusted  Conversion  Price in  accordance  herewith and
            shall prepare a report  setting forth such  adjustment.  The Company
            will  promptly  (and,  in any event,  not later than such  fifteenth
            (15th) day) furnish a copy of each such report and such verification
            to the holder of any Series A Preferred Share. The Company will also
            keep  copies  of all  such  reports  and such  verifications  at its
            principal  office,  and  will  cause  the same to be  available  for
            inspection at such office during normal business hours by the holder
            of any Series A Preferred Shares.

                  (xii) Notice of Certain Corporate Action. In case:

                        (1) the Company  shall  declare a dividend (or any other
                  distribution)  on its Common Stock payable  otherwise  than in
                  cash out of its earned surplus; or

                        (2) (a) of any  reclassification  of the Common Stock of
                  the  Company,  or (b) of any  consolidation,  merger  or share
                  exchange  to  which  the  Company  is a party  and  for  which
                  approval of any  stockholders  of the Company is required,  or
                  (c) of the  conveyance,  transfer,  sale  or  lease  of all or
                  substantially all of the assets of the Company; or

                        (3)  of  the  voluntary  or   involuntary   dissolution,
                  liquidation or winding up of the Company;

            then the Company,  ten (10)  business  days prior to the  applicable
            record,  expiration or effective date hereinafter  specified,  shall
            give to each  holder of Series A Preferred  Shares a notice  stating
            (x) the date on which a record  is to be taken  for the  purpose  of
            such dividend, distribution,  rights or warrants, or, if a record is
            not to be  taken,  the  effective  date as of which the  holders  of
            Common   Stock  of  record  to  be   entitled   to  such   dividend,
            distribution,  rights or warrants are to be determined, (y) the date
            on  which  such  reclassification,   consolidation,   merger,  share
            exchange,   conveyance,    transfer,   sale,   lease,   dissolution,
            liquidation or winding up is expected to become  effective,  and the
            date as of which it is  expected  that  holders  of Common  Stock of
            record  shall be entitled to exchange  their  shares of Common Stock
            for  securities,  cash  or  other  property  deliverable  upon  such
            reclassification, consolidation, merger, share exchange, conveyance,
            transfer, sale, lease, dissolution, liquidation or winding up.

            (h) On  presentation  and surrender to the Company (or at any office
      or agency maintained for the transfer of the Series A Preferred Shares) of
      the  certificates  of Series A Preferred  Shares so to be converted,  duly
      endorsed in blank for transfer or 


                                       7


      accompanied  by proper  instruments  of assignment or transfer in blank (a
      "Conversion  Notice"),  with  signatures  guaranteed,  the  holder of such
      Series A Preferred  Shares shall be entitled,  subject to the  limitations
      herein  contained,  to  receive in  exchange  therefor  a  certificate  or
      certificates for fully paid and nonassessable  shares,  which certificates
      shall be delivered by the fifth  trading day after the date of delivery of
      the Conversion  Notice, and cash for fractional shares, of Common Stock on
      the foregoing basis. The Series A Preferred Shares shall be deemed to have
      been  converted,  and the person  converting  the same to have  become the
      holder  of  record of Common  Stock,  for all  purposes  as of the date of
      delivery of the Conversion Notice.

            (i) The  Company  shall,  so long as any of the  Series A  Preferred
      Shares are  outstanding,  reserve and keep available out of its authorized
      and  unissued  Common  Stock,  solely  for the  purpose of  effecting  the
      conversion of the Series A Preferred  Shares  outstanding,  such number of
      shares of Common Stock as it shall  reasonably  believe shall from time to
      time be  sufficient  to  effect  the  conversion  of all of the  Series  A
      Preferred Shares then outstanding.

            (j) The  Company  shall pay any and all taxes  which may be  imposed
      upon it with respect to the issuance and delivery of Common Stock upon the
      conversion  of the  Series A  Preferred  Shares  as herein  provided.  The
      Company  shall not be required  in any event to pay any  transfer or other
      taxes by reason of the  issuance of such Common  Stock in names other than
      those in which the Series A Preferred  Shares  surrendered  for conversion
      are  registered  on the  Company's  records,  and no  such  conversion  or
      issuance  of Common  Stock  shall be made  unless  and  until  the  person
      requesting  such  issuance  has paid to the Company the amount of any such
      tax,  or has  established  to the  satisfaction  of the  Company  and  its
      transfer agent, if any, that such tax has been paid.

      (3) Voting  Rights.  Holders of Series A  Preferred  Shares  shall have no
voting rights, except as required by law, by Section 7 hereof and, to the extent
permitted by applicable laws and regulations,  as provided in this Section 3. If
during any fiscal year of the  Company,  the Company  shall be in arrears in the
payment of any  dividend  on the Series A  Preferred  Shares for a period of six
months  or  more  during  such  fiscal  year,  then  at the  annual  meeting  of
shareholders relating to such fiscal year, the holders of the Series A Preferred
Shares  shall have the right to  designate a nominee for director to be included
on the slate of the Company's  nominees for directors for such annual meeting of
shareholders,  and further,  shall have the right,  voting as a class,  to elect
such  nominee  as  a  director  of  the  Company  at  such  annual   meeting  of
shareholders.

      (4)  Redemption.  The Company may,  but shall not be obligated  to, at any
time, and from time to time, redeem on the terms and conditions herein provided,
the whole or any part of the Series A  Preferred  Shares then  outstanding  at a
redemption price of $120 per Preferred Share,  plus accrued and unpaid dividends
thereon, in accordance with the following procedures:


                                       8


            (a) In case of  redemption  of only part of the  Series A  Preferred
      Shares at any time outstanding,  the Company shall designate the amount of
      Series A Preferred Shares so to be redeemed and shall redeem such Series A
      Preferred Shares ratably from each tranche.

            (b)  Notice  of  every  redemption  shall  be given by mail to every
      holder of record of any Series A Preferred Shares then to be redeemed,  at
      least  thirty (30),  but no more than ninety (90),  days prior to the date
      fixed as the date for the redemption thereof, at the respective  addresses
      of such  holders as the same shall appear on the stock  transfer  books of
      the  Company.  The notice  shall state that the Series A Preferred  Shares
      shall be redeemed by the Company at the redemption  price specified above,
      upon the surrender for  cancellation,  at the time and place designated in
      such  notice,  of the  certificates  representing  the Series A  Preferred
      Shares  to be  redeemed,  properly  endorsed  in blank  for  transfer,  or
      accompanied  by proper  instruments  of assignment  and transfer in blank,
      with signatures guaranteed,  and bearing all necessary transfer tax stamps
      thereto  affixed  and  canceled.  On and after the date  specified  in the
      notice  described  above,  each holder of Series A Preferred Shares called
      for  redemption  shall be  entitled  to  receive  therefor  the  specified
      redemption  price upon  presentation and surrender at the place designated
      in such notice of the  certificates  for Series A Preferred  Shares called
      for redemption,  properly endorsed in blank for transfer or accompanied by
      proper  instruments  of assignment or transfer in blank,  with  signatures
      guaranteed,  and bearing all necessary transfer tax stamps thereto affixed
      and canceled.

            (c) If the Company shall give notice of redemption as aforesaid (and
      unless the Company shall fail to pay the redemption  price of the Series A
      Preferred Shares presented for redemption in accordance with such notice),
      all Series A Preferred  Shares  called for  redemption  shall be deemed to
      have been  redeemed on the date  specified in such notice,  whether or not
      the  certificates  for such Series A Preferred Shares shall be surrendered
      for  redemption,  and  such  Series  A  Preferred  Shares  so  called  for
      redemption  shall from and after such date cease to represent any interest
      whatsoever in the Company or its property,  and the holders  thereof shall
      have no rights  other  than the right to  receive  such  redemption  price
      without any interest thereof from and after such date.

      (5) Liquidation, Dissolution, Winding Up. In the event of any voluntary or
involuntary  liquidation,  dissolution or winding up of the Company, the holders
of the Series A Preferred Shares shall be entitled to receive in cash out of the
assets of the  Company,  whether from capital or from  earnings,  available  for
distribution  to its  stockholders  (the "Preferred  Funds"),  before any amount
shall be paid to the  holders of the Common  Stock or holders of shares of other
classes or series of capital  stock of the Company  (the  "Junior  Shares"),  an
amount equal to the Stated Value per Series A Preferred Share  outstanding  plus
accrued and unpaid dividends thereon,  provided that, if the Preferred Funds are
insufficient  to pay the full  amount due to the  holders of Series A  Preferred
Shares, then each holder of Series A Preferred Shares shall receive a percentage
of the  Preferred  Funds equal to the full amount of Preferred  Funds payable to
such holder as a percentage of the full amount of Preferred Funds payable to all
holders of Series A Preferred Shares.  The purchase or redemption by the Company
of stock of any  class,  in any manner  permitted  by law,  shall  not,  for the
purposes hereof, be regarded as a liquidation,  dissolution or winding up of the
Company.  Notwithstanding  the foregoing,  to the extent that Series A Preferred
Shares shall be converted or 


                                       9


redeemed,  as the case may be, the Company may issue shares of other  classes or
series of preferred  stock of the Company that are of equal rank with the Series
A Preferred  Shares (the "Pari Passu Shares"),  and such Pari Passu Shares shall
be entitled to  distributions  of the  Preferred  Funds on the same basis as the
Series A Preferred  Shares.  Neither the consolidation nor merger of the Company
with or into any other corporation or corporations,  nor the sale or transfer by
the  Company  of less  than  substantially  all of its  assets,  shall,  for the
purposes hereof, be deemed to be a liquidation, dissolution or winding up of the
Company. No holder of Series A Preferred Shares shall be entitled to receive any
amounts with respect thereto upon any liquidation,  dissolution or winding up of
the Company other than the amounts provided for herein.

      (6) Preferred Rank.  Except with respect to any Pari Passu Shares that the
Company  may  issue  from  time to time  pursuant  to  Section  5, all  Series A
Preferred  Shares shall be of senior rank to all Junior Shares in respect to the
preferences as to dividends and distributions and payments upon the liquidation,
dissolution or winding up of the Company. In the event dividends on the Series A
Preferred  Shares are in  arrears,  the  Company  shall not be  entitled  to pay
dividends on any,  Junior Shares or Pari Passu Shares.  The rights of the Junior
Shares shall be subject to the  preferences  and relative rights of the Series A
Preferred Shares.  Notwithstanding the foregoing,  the Company may authorize and
issue additional or other preferred stock which is of junior rank, or equal rank
as permitted by Section 5, with the Series A Preferred  Shares in respect of the
preferences as to dividends and distributions and payments upon the liquidation,
dissolution or winding up of the Company; provided, however, that for so long as
the Series A Preferred Shares remain outstanding the Company shall not issue any
capital  stock  which is  senior  in rank to the  Series A  Preferred  Shares in
respect  of any of the  foregoing  preferences.  In the  event of the  merger or
consolidation  of the Company  with or into  another  corporation,  the Series A
Preferred  Shares  shall  maintain  their  relative  powers,   designations  and
preferences provided for herein.

      (7) Vote to Change the Terms of Series A Preferred Shares. The affirmative
vote at a meeting duly called for such purpose or the written  consent without a
meeting of the holders of not less than two-thirds (2/3) of the then outstanding
Series A Preferred  Shares shall be required to amend,  alter,  change or repeal
any of the  powers,  designations,  preferences  and  rights  of  the  Series  A
Preferred Shares.


                                       10


      IN WITNESS  WHEREOF,  the Company has caused this certificate to be signed
by, its President, and its Secretary, this 3rd day of December 1997.

                                          IMCLONE SYSTEMS INCORPORATED

                                          By: /s/ Samuel D. Waksal
                                             ---------------------------------
                                          Name:   Samuel D. Waksal
                                               -------------------------------
                                          Title:  President & CEO
                                                ------------------------------

ATTEST

By: /s/ John B. Landes
   ---------------------------------
Name:   John B. Landes
     -------------------------------
Title:  Secretary
      ------------------------------


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