<PAGE>
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. _____1_____)*
Simon Transportation Services, Inc.
-----------------------------------
(Name of Issuer)
Common Stock
------------
(Title of Class of Securities)
82881310
--------
(CUSIP Number)
December 31, 1998
-----------------
(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to
which this Schedule is filed:
[X] Rule 13d-1(b)
[ ] 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 the
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).
Page 1 of 4 Pages
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- ------------------------------- -------------------------------
CUSIP No. 82881310 13G Page 2 of 4 Pages
- ------------------------------- -------------------------------
- --------------------------------------------------------------------------------
1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Warburg Pincus Asset Management, Inc. 13-2673503
- --------------------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
(a) [ ]
(b) [ ]
Not applicable
- --------------------------------------------------------------------------------
3 SEC USE ONLY
- --------------------------------------------------------------------------------
4 CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
- --------------------------------------------------------------------------------
5 SOLE VOTING POWER
Not applicable
------------------------------------------------------------------
NUMBER OF 6 SHARED VOTING POWER
SHARES
BENEFICIALLY Not applicable
OWNED BY
EACH ------------------------------------------------------------------
REPORTING 7 SOLE DISPOSITIVE POWER
PERSON
WITH Not Applicable
------------------------------------------------------------------
8 SHARED DISPOSITIVE POWER
Not applicable
- --------------------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
Not applicable
- --------------------------------------------------------------------------------
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
(SEE INSTRUCTIONS)
[ ]
Not Applicable
- --------------------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
Not applicable
- --------------------------------------------------------------------------------
12 TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
IA
- --------------------------------------------------------------------------------
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Item 1(a): Name of Issuer:
- ---------- ---------------
Simon Transportation Services, Inc.
Item 1(b): Address of Issuer's Principal Executive Offices:
- ---------- ------------------------------------------------
5175 West 2100 South
West Valley City, UT 84120
Item 2(a) Name of Person Filing
- --------- ---------------------
Warburg Pincus Asset Management, Inc.
Item 2(b): Address of Principal Business Office:
- ---------- -------------------------------------
466 Lexington Avenue, New York, New York 10017
Item 2(c): Citizenship:
- ---------- ------------
Delaware
Item 2(d): Title of Class of Securities:
- ---------- -----------------------------
Common Stock
Item 2(e): CUSIP Number:
- ---------- -------------
82881310
Item 3: If the reporting person is an investment adviser in
- ------- accordance with ss. 240.13d-1(b)(1)(ii)(E), check
this box. [X]
Item 4: Ownership:
- ------- ----------
Not applicable
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
the following [X]
Item 6: Ownership of More than Five Percent on Behalf of
- ------- ------------------------------------------------
Another Person:
---------------
Not applicable
Page 3 of 4 Pages
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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:
---------------------
Not Applicable.
Item 9: Notice of Dissolution of Group:
- ------- -------------------------------
Not Applicable.
Item 10: Certification:
- -------- --------------
Inasmuch as the reporting person is no longer the
beneficial owner of more than five percent of the
number of shares outstanding of the issuer of the
securities referenced herein, the reporting person
has no further reporting obligation under Section
13(d) of the Act with respect to such issuer.
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: February 1, 1999
By: /s/ Linda S. Iovan
----------------------
Name: Linda S. Iovan
Title: Vice President
Page 4 of 4 Pages
