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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. 4)
PharmChem Laboratories, Inc.
(Name of Issuer)
Common Stock
(Title of Class of Securities)
717133102
(CUSIP Number)
June 14, 1999
(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this
Schedule is filed:
/___/ Rule 13d-1(b)
/ X / Rule 13d-1(c)
/___/ Rule 13d-1(d)
* 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 disclosures provided in a prior cover page.
The information required on 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).
Potential persons who are to respond to the collection of information
contained in this form are not required to respond unless the form displays
a currently valid OMB control number.
SEC 1745 (3-98) Page 1 of 6
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CUSIP No. 717133102 Page 2 of 6 Pages
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1 NAME OF REPORTING PERSONS
IRS IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)
Micro Cap Partners, L.P.
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2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions)
(a)/ X /
(b)/ /
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3 SEC USE ONLY
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4 CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
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NUMBER OF 5 SOLE VOTING POWER
SHARES 0
BENEFICIALLY ---------------------------------------
OWNED BY 6 SHARED VOTING POWER
EACH 320,400
REPORTING ---------------------------------------
PERSON 7 SOLE DISPOSITIVE POWER
WITH 0
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8 SHARED DISPOSITIVE POWER
320,400
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9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
320,400
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10 CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
CERTAIN SHARES (See Instructions)
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11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
5.5
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12 TYPE OF REPORTING PERSON (See Instructions)
PN
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CUSIP No. 717133102 13G Page 3 of 6 Pages
ITEM 1.
(a) The name of the issuer is PharmChem Laboratories, Inc. (the
"Issuer").
(b) The principal executive office of the Issuer is located at
1505A O'Brien Drive, Menlo Park, CA 94025.
ITEM 2.
(a) The name of the person filing this statement is Micro Cap
Partners, L.P. (the "Filer").
(b) The principal business office of the Filers is located at
470 University Avenue, Palo Alto, CA 94301.
(c) See Item 4 of the cover sheet for the Filer.
(d) This statement relates to shares of common stock of the Issuer
(the "Stock").
(e) The CUSIP number of the Stock is 717133102.
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CUSIP No. 717133102 Page 4 of 6 Pages
ITEM 3. If this statement is filed pursuant to rule 240.13d-1(b) or
240.13d-2(b) or (c), check whether the person filing is a:
(a) ___ Broker or dealer registered under section 15 of the Act (15
U.S.C. 78o).
(b) ___ Bank as defined in section 3(a)(6) of the Act (15 U.S.C.
78c).
(c) ___ Insurance company as defined in section 3(a)(19) of the Act
(15 U.S.C. 78c).
(d) ___ Investment company registered under section 8 of the
Investment Company Act of 1940 (15 U.S.C. 80a-8).
(e) ___ An investment adviser in accordance with 240.13d-
1(b)(1)(ii)(E).
(f) ___ An employee benefit plan or endowment fund in accordance
with 240.13d-1(b)(1)(ii)(F).
(g) ___ A parent holding company or control person in accordance
with 240.13d-1(b)(1)(ii)(G)
(h) ___ A savings association as defined in section 3(b) of the
Federal Deposit Insurance Act (12 U.S.C. 1813).
(i) ___ A church plan that is excluded from the definition of an
investment company under section 3(c)(14) of the Investment Company Act of
1940 (15 U.S.C. 80a-3).
(j) ___ Group, in accordance with section 240.13d-1(b)(1)(ii)(J)
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CUSIP No. 717133102 13G Page 5 of 6 Pages
ITEM 4. OWNERSHIP
See Items 5-9 and 11 on the cover sheet for the Filer.
ITEM 5. OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS
If this statement is being filed to report the fact that as of the date
hereof the reporting person has ceased to be the beneficial owner of more
than five percent of the class of securities, check the following /___/.
ITEM 6. OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON
Not applicable
ITEM 7. IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED
THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY
Not applicable.
ITEM 8. IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP
The Filer's holdings of the Stock are managed by Palo Alto Investors
("PAI"), a registered investment adviser that is the general partner of the
Filer. PAI and William L. Edwards, PAI's controlling shareholder, have
filed a separate Schedule 13G with respect to the Stock.
ITEM 9. NOTICE OF DISSOLUTION OF GROUP
Not applicable.
ITEM 10. CERTIFICATION
By signing below I certify that, to the best of my knowledge and belief,
the securities referred to above were not acquired and are not held for the
purpose of or with the effect of changing or influencing the control of the
issuer of the securities and were not acquired and are not held in
connection with or as a participant in any transaction having that purpose
or effect.
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CUSIP No. 717133102 13G Page 6 of 6 Pages
SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete
and correct.
Dated: June 18, 1999
MICRO CAP PARTNERS, L.P.
By: Palo Alto Investors
General Partner
By: /s/ William L. Edwards
William L. Edwards, President
BLD/4325/002/1027803
