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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13D
Under the Securities Exchange Act of 1934
(Amendment No. 1)*
Name of Issuer: IDEC Pharmaceuticals Corporation
Title of Class of Securities: Common Stock
CUSIP Number: 449370105
(Name, Address and Telephone Number of Person
Authorized To Receive Notices and Communications)
Norman S. Schleifer
c/o Oracle Partners, L.P.
712 Fifth Avenue, 45th Floor
New York, New York 10019
(Date of Event which Requires Filing of this Statement)
July 17, 1997
If the filing person has previously filed a statement on Schedule
13G to report the acquisition which is the subject of this
Schedule 13D, and is filing this schedule because of
Rule 13d-1(b)(3) or (4), check the following box [ ].
*The remainder of this cover page shall be filled out for a
reporting person's initial filing on this form with respect to
the subject class of securities, and for any subsequent amendment
containing information which would alter the disclosures provided
in a prior cover page.
The information required in the remainder of this cover page
shall not be deemed to be "filed" for the purpose of Section 18
of the Securities Exchange Act of 1934 ("Act") or otherwise
subject to the liabilities of that section of the Act but shall
be subject to all other provisions of the Act (however, see the
Notes).
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CUSIP No.: 449370105
1. Name of Reporting Person
I.R.S. Identification No. of Above Person
Larry N. Feinberg
2. Check the Appropriate Box if a Member of a Group
a.
b.
3. SEC Use Only
4. Source of Funds
WC
5. Check if Disclosure of Legal Proceedings is Required Pursuant
to Items 2(d) or 2(e)
6. Citizenship or Place of Organization
United States
Number of Shares Beneficially Owned by Each Reporting Person
With:
7. Sole Voting Power:
1,538,600
8. Shared Voting Power:
9. Sole Dispositive Power:
1,538,600
10. Shared Dispositive Power:
11. Aggregate Amount Beneficially Owned by Each Reporting Person
1,538,600
12. Check Box if the Aggregate Amount in Row (11) Excludes
Certain Shares
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13. Percent of Class Represented by Amount in Row (11)
8.18%
14. Type of Reporting Person
IN
*SEE INSTRUCTIONS BEFORE FILLING OUT!
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Item 1. Security and Issuer
This Amendment No. 1 to Schedule 13D relates to
shares of common stock (the "Common Stock") of IDEC
Pharmaceuticals Corporation ("IDEC"). IDEC's principal
executive office is located at 11011 Torreyana Road, San
Diego, CA 92121.
Item 2. Identity and Background
This statement is being filed on behalf of Mr.
Larry N. Feinberg. Mr. Feinberg is the managing general
partner of Oracle Partners, L.P. and Oracle Institutional
Partners, L.P., both of which are investment limited
partnerships (the "Partnerships"), and has investment
discretion over certain managed accounts. The principal
offices of the Partnerships are at 712 Fifth Avenue, 45th
Floor, New York, New York 10019.
Mr. Feinberg has not during the last five years,
been convicted in a criminal proceeding (excluding traffic
violations or similar misdemeanors). Mr. Feinberg has not
during the last five years, been a party to a civil
proceeding of a judicial or administrative body of competent
jurisdiction which resulted in a judgment, decree or final
order enjoining future violations of, or prohibiting or
mandating activities subject to, federal or state securities
laws or finding any violations with respect to such laws.
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Mr. Feinberg is a citizen of the United States of
America.
Item 3. Source and Amount of Funds or Other Consideration
As of the date hereof, Mr. Feinberg is deemed to
beneficially own 1,538,600 shares of IDEC's Common Stock
(the "Shares"). The Shares are held by the Partnerships and
by managed accounts over which Mr. Feinberg has investment
discretion. The 1,538,600 Shares were purchased in open
market transactions. The funds for the purchase of the
Shares held in the Partnerships, over which Mr. Feinberg has
investment discretion, came from capital contributions to
the Partnerships by their general and limited partners. The
funds for the purchase of the Shares held in the managed
accounts, over which Mr. Feinberg has investment discretion,
came from each managed account's own funds. No leverage was
used to purchase the Shares.
Item 4. Purpose of Transaction
The Shares deemed to be beneficially owned by Mr.
Feinberg were acquired for, and are being held for,
investment purposes. Mr. Feinberg may acquire additional
shares of Common Stock, dispose of all or some of the Shares
from time to time, in each case in open market transactions,
block sales or purchases or otherwise, or may continue to
hold the Shares.
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Mr. Feinberg does not have any plan or proposal
which relates to, or would result in, any of the actions
enumerated in Item 4 of the instructions to Schedule 13D.
However, Mr. Feinberg reserves the right to discuss company
business with management, make proposals to management
and/or take other actions to influence the management of
IDEC should he deem such actions appropriate.
Item 5. Interest in Securities of the Issuer
As of the date hereof, Mr. Feinberg is deemed to be
the beneficial owner of 1,538,600 shares of IDEC's Common
Stock. Based on information received from the management of
IDEC, there are believed to be 18,796,285 shares of IDEC's
Common Stock outstanding. Therefore, Mr. Feinberg is deemed
to beneficially own 8.18% of IDEC's outstanding shares of
Common Stock. Mr. Feinberg has the power to vote, direct
the vote, dispose of or direct the disposition of all the
shares of IDEC's Common Stock that he is currently deemed to
beneficially own.
Item 6. Contracts, Arrangements, Understandings or
Relationships With Respect to Securities of
the Issuer
Mr. Feinberg does not have any contract,
arrangement, understanding or relationship with any person
with respect to the Common Stock of IDEC.
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Item 7. Material to be Filed as Exhibits
Attached hereto as Exhibit A is a description of
the transactions in the Common Stock of IDEC that were
effected by Mr. Feinberg during the past 60 days.
Signature
The undersigned, after reasonable inquiry and to
the best of his knowledge and belief, certifies that the
information set forth in this statement is true, complete
and correct.
July 23, 1997
/s/ Larry N. Feinberg
________________________________
Larry N. Feinberg
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EXHIBIT A
Daily Transactions
Common Stock
Trade Date Number of Shares Price Per Share Value
05/29/97 10,000 22.875 $ 228,750
06/02/97 50,000 25.000 1,250,000
06/04/97 2,500 25.25 63,125
06/05/97 4,500 25.944 116,748
06/05/97 28,000 27.4464 768,499
06/06/97 25,000 27.75 693,750
06/18/97 50,000 27.85 1,392,500
07/16/97 40,000 26.7656 1,070,624
07/16/97 25,000 26.30 657,500
07/17/97 25,000 27.25 681,250
07/21/97 50,000* 28.315 1,415,750
07/22/97 60,000* 28.96 1,737,600
____________________
* These shares represent call options exercisable for Common
Stock within 60 days of this filing.
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00751001.AS1