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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. )*
Name of Issuer: Dianon Systems, Inc.
Title of Class of Securities: Common Stock, par value $.01 per
share
CUSIP Number: 252826102
(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)
April 9, 1999
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.: 252826102
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. X
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:
348,636
8. Shared Voting Power:
376,364
9. Sole Dispositive Power:
348,636
10. Shared Dispositive Power:
376,364
11. Aggregate Amount Beneficially Owned by Each Reporting Person
725,000
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)
11.04%
14. Type of Reporting Person
IN
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CUSIP No.: 252826102
1. Name of Reporting Person
I.R.S. Identification No. of Above Person
Oracle Partners, L.P.
2. Check the Appropriate Box if a Member of a Group
a.
b. X
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
Delaware
Number of Shares Beneficially Owned by Each Reporting Person
With:
7. Sole Voting Power:
8. Shared Voting Power:
371,364
9. Sole Dispositive Power:
10. Shared Dispositive Power:
371,364
11. Aggregate Amount Beneficially Owned by Each Reporting Person
371,364
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)
5.65%
14. Type of Reporting Person
PN
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Item 1. Security and Issuer
This statement relates to shares of the Common Stock,
par value $.01 per share (the "Shares") of Dianon Systems, Inc.
(the "Issuer"). The Issuer's principal executive office is
located at 200 Watson Boulevard, Stratford, Connecticut 06615.
Item 2. Identity and Background
This statement is being filed on behalf of Mr. Larry N.
Feinberg and Oracle Partners, L.P. (collectively, the "Reporting
Persons"). Mr. Feinberg is the managing general partner of
Oracle Partners, L.P.(the "Partnership") and Oracle Institutional
Partners, L.P., both of which are investment limited
partnerships, and the President of Oracle Investment Management,
Inc., an investment adviser that has investment discretion over
certain managed accounts. The principal office of the Reporting
Persons is at 712 Fifth Avenue, 45th Floor, New York, New York
10019.
Neither of the Reporting Persons have during the last
five years, been convicted in a criminal proceeding (excluding
traffic violations or similar misdemeanors). Neither of the
Reporting Persons have 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. The Partnership is a Delaware limited partnership.
Item 3. Source and Amount of Funds or Other Consideration
As of the date hereof, Mr. Feinberg is deemed to
beneficially own 725,000 Shares, of which the Partnership is the
beneficial owner of 371,364 Shares. The Shares of which Mr.
Feinberg is deemed to benefically own are held by: (i) the
Partnership, other investment partnerships and managed accounts
over which Mr. Feinberg has investment discretion; (ii) by Mr.
Feinberg and other investment professionals of Oracle Investment
Management individually; and (iii) by a retirement plan of Oracle
Investment Management over which Mr. Feinberg has investment
discretion.
The 725,000 Shares were purchased in open market
transactions at an aggregate cost of $5,371,354. The funds for
the purchase of the Shares held by the Partnership and other
investment partnerships came from capital contributions to such
partnerships by their respective general and limited partners.
The funds for the purchase of the Shares held in the managed
accounts came from each managed account's own funds. The funds
for the purchase of the Shares held by Mr. Feinberg, other
investment professionals and the retirement plan came from direct
contributions from such persons. No leverage was used to
purchase the Shares.
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Item 4. Purpose of Transaction
The Shares deemed to be beneficially owned by the
Reporting Persons were acquired for, and are being held for,
investment purposes. The Reporting Persons may acquire
additional Shares, 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.
The Reporting Persons do 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, the Reporting Persons reserve the right to discuss
company business with management, make proposals to management
and/or take other actions to influence the management of Issuer
should they 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 725,000 Shares, of which the Partnership
beneficially owns 371,365 Shares. Based on the Issuer's most
recent Form 10-K, as of March 4, 1999, there were 6,567,915
Shares outstanding. Therefore, Mr. Feinberg is deemed to
beneficially own 11.04% and the Partnership beneficially owns
5.65% of the outstanding Shares. Mr. Feinberg has sole power to
vote, direct the vote, dispose of or direct the disposition of
348,636 Shares. Mr. Feinberg has shared power to vote, direct
the vote, dispose of or direct the disposition of 376,364 Shares.
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The Partnership has shared power to vote, direct he vote, dispose
of or direct the disposition of 371,364 Shares.
Item 6. Contracts, Arrangements, Understandings or
Relationships With Respect to Securities of
the Issuer
The Reporting Persons have no contract, arrangement,
understanding or relationship with any person with respect to the
Shares.
Item 7. Material to be Filed as Exhibits
1. An agreement relating to the filing of a joint
statement as required by Rule 13d-1(f) under
the Securities Exchange Act of 1934 is filed
herewith as Exhibit A.
2. A description of the transactions in the
Shares that were effected by the Reporting
Persons during the past 60 days is filed
herewith as Exhibit B.
Signature
The undersigned, after reasonable inquiry and to the
best of their knowledge and belief, certifies that the
information set forth in this statement is true, complete and
correct.
April 15, 1999
/s/ Larry N. Feinberg
________________________________
Larry N. Feinberg
ORACLE PARTNERS, L.P.
/s/ Larry N. Feinberg
_________________________________
By: Larry N. Feinberg
General Partner
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Exhibit A
AGREEMENT
The undersigned agree that this Schedule 13D dated
April 15, 1999 relating to the Common Stock of Dianon Systems,
Inc. shall be filed on behalf of the undersigned.
/s/ Larry N. Feinberg
________________________________
Larry N. Feinberg
ORACLE PARTNERS, L.P.
/s/ Larry N. Feinberg
________________________________
By: Larry N. Feinberg
General Partner
00751001.BC2
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Exhibit B
SCHEDULE OF TRANSACTIONS
Price Per Share
Date Shares Purchased or (Sold) (excluding Commission)
3/31/99 10,000 $8.750
4/9/99 15,000 8.125
4/12/99 11,600 8.375
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00751001.BC2
