UNITED STATES SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, DC 20549
FORM 4
STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP
( ) Check this box if no longer subject to Section 16.
1. Name and Address of Reporting Person
Kelley, Paul J.
2312 The Woods Lane
Lexington, KY 40502
2. Issuer Name and Ticker or Trading Symbol
Martek Biosciences Corporation (MATK)
3. IRS or Social Security Number of Reporting Person (Voluntary)
4. Statement for Month/Year
5/2000
5. If Amendment, Date of Original (Month/Day/Year)
6. Relationship of Reporting Person(s) to Issuer (Check all applicable)
( ) Director ( ) 10% Owner
(X) Officer (give title below) ( ) Other (specify below)
Officer
7. Individual or Joint/Group Filing (Check Applicable Line)
(X) Form filed by One Reporting Person
( ) Form filed by More than One Reporting Person
<TABLE>
TABLE I -- Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
<CAPTION>
+---------------------------------+----------+-------------+-----------------------------+----------------+-----------+------------+
|1. Title of Security |2. Trans- |3. Trans- |4. Securities Acquired (A) |5. Amount of |6. Owner- |7. Nature |
| | action | action | or Disposed of (D) | Securities | ship | of In- |
| | Date | Code | | Beneficially | Form: | direct |
| | | | | Owned at | Direct | Bene- |
| | (Month/ | | | End of | (D) or | ficial |
| | Day/ +-------+-----+-----------+------+----------+ Month | Indirect| Owner- |
| | Year) |Code |V |Amount |A/D |Price | | (I) | ship |
+---------------------------------+----------+-------+-----+-----------+------+----------+----------------+-----------+------------+
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C>
Common Stock 05/02/2000 M 2000 A $6.250000 D
Common Stock 05/02/2000 S -1700 D $15.687500 D
Common Stock 05/02/2000 S -100 D $15.750000 D
Common Stock 05/02/2000 S -200 D $15.875000 D
Common Stock 05/26/2000 M 1500 A $14.437000 D
Common Stock 05/26/2000 M 2000 A $6.250000 D
Common Stock 05/26/2000 M 1500 A $16.500000 D
Common Stock 05/26/2000 S -5000 D $18.937000 0 D
</TABLE>
<PAGE>
<TABLE>
TABLE II -- Derivative Securities Acquired, Disposed of, or Beneficially Owned
<CAPTION>
+-------------+--------+----------+---------+-----------+---------------------+----------------+----------+--------+-------+-------+
|1. |2. |3. |4. |5. |6. |7. |8. |9. |10. |11. |
| | | | | | | | |Number |Owner- | |
| | | | | | | | |of |ship | |
| | | | | | | | |Deriv- |Form of| |
| | | | | | |Title and Amount| |ative |Deriv- | |
| | | | | | |of Underlying | |Secur- |ative |Nature |
| |Conver- | | |Number of | |Securities | |ities |Secur- |of |
| |sion or | | |Derivative |Date Exercisable +-------+--------+ |Benefi- |ity: |In- |
| |Exercise| | |Securities |and Expiration Date | |Amount | |cially |Direct |direct |
| |Price of|Transac- |Transac- |Acquired(A)|(Month/Day/Year) | |or | |Owned |(D) or |Bene- |
|Title of |Deriv- |tion Date |tion Code|Disposed(D)+----------+----------+ |Number |Price of |at End |In- |ficial |
|Derivative |ative |(Month/ +------+--+-----+-----+Date Exer-|Expira- | |of |Derivative|of |direct |Owner- |
|Security |Security|Day/Year) |Code |V |(A) |(D) |cisable |tion Date |Title |Shares |Security |Month |(I) |ship |
+-------------+--------+----------+------+--+-----+-----+----------+----------+-------+--------+----------+--------+-------+-------+
<S> <C> <C> <C> <C><C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
Stock Options $6.25 05/02/2000 M 2000 09/11/1999 03/11/2009 Common 2000 $6.250000 D
(Right to buy) Stock
Stock Options $6.25 05/26/2000 M 2000 09/11/1999 03/11/2009 Common 2000 $6.250000 24000 D
(Right to buy) Stock
Stock Options $14.437 05/26/2000 M 1500 09/05/1998 03/04/2008 Common 1500 $14.437000 8500 D
(Right to buy) Stock
Stock Options $16.5 05/26/2000 M 1500 04/01/1998 03/31/2007 Common 1500 $16.500000 8500 D
(Right to buy) Stock
</TABLE>
Explanation of Responses:
SIGNATURE OF REPORTING PERSON
/s/ Paul J. Kelley
DATE
06/06/2000
