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UNITED STATES SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
FORM 3
INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES
1. Name and Address of Reporting Person
Larry N. Feinberg
712 Fifth Avenue
45th Floor
New York, New York 10019
2. Date of Event Requiring Statement (Month/Day/Year)
March 31, 1999
3. IRS Number of Reporting Person
(Voluntary)
4. Issuer Name and Ticker or Trading Symbol
Dianon Systems, Inc.
DIAN
5. Relationship of Reporting Person(s) to Issuer (Check all
applicable)
( ) Director (X) 10% Owner ( ) Officer (give title
below) ( ) Other
(specify below)
6. If Amendment, Date of Original (Month/Day/Year)
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 I -- Non-Derivative Securities Beneficially Owned
1. Title of Security 2. Amount of 3. Ownership 4. Nature of Indirect
Securities Form: Beneficial Ownership
Beneficially Direct(D) or
Owned Indirect(I)
Common Stock 45,600 (D)
Common Stock 679,400 + (I) General Partner,
Principal of Investment
Manager or Trustee.
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Table II -- Derivative Securities Beneficially Owned
<TABLE>
<S> <C> <C> <C> <C> <C>
1.Title of 2.Date Exer- 3.Title and Amount 4. Conver- 5. Ownership 6. Nature of
Derivative cisable and of Securities sion or Form of Indirect
Security Expiration Underlying Exercise Derivative Beneficial
Date Derivative Security Price of Security:
Ownership
(Month/Day/ --------------- Deri- Direct(D) or
Year) Title Amount or vative Indirect (I)
--------------- Number of Security
Date Expira- Shares
Exer- tion
cisable Date
NOT APPLICABLE
</TABLE>
Explanation of Responses:
+ The Reporting Person disclaims beneficial ownership of these
securities except to the extent of his pecuniary interest
therein.
SIGNATURE OF REPORTING PERSON
/s/ Larry N. Feinberg
___________________________
Larry N. Feinberg
April 15, 1999
00751001.BC3
2
