Rule 424(b)(3)
File No. 33-38033
NALCO CHEMICAL COMPANY
COMMON STOCK ACQUIRED UNDER THE
NALCO CHEMICAL COMPANY
1990 STOCK OPTION PLAN
APPENDIX DATED MAY 12, 1997
TO PROSPECTUS DATED NOVEMBER 30, 1990
This Appendix updates certain information in the Prospectus dated November 30,
1990 (the "Prospectus") relating to shares of Common Stock which may be offered
by the stockholders listed herein under the caption "Selling Stockholders" or by
their transferees (or by their donees or pledgees). The Company will furnish
without charge to participants additional copies of the Prospectus upon request.
SELLING STOCKHOLDERS
The following table sets forth the name and position within the Company for the
last three years of each Selling Stockholder, the number of shares of Common
Stock of the Company beneficially owned by him on the date of this Prospectus
and, the number of shares offered by the Prospectus.
Shares Offered
Shares By This
Name and Position Owned (1)(2) Prospectus (2)
E. J. Mooney 358,280 378,600
President and Chief Operating
Officer from January, 1992 to
March 1994; President as of
March, 1990; Chief Executive Officer
as of April, 1994; and Chairman as of July,
1994.
(1) Includes 314,334 shares which are subject to outstanding stock options
exercisable within sixty days of April 30, 1997.
(2) Includes shares which may be acquired by exercise of stock options.
Additional Selling Stockholders will be identified by a subsequent appendix. One
or more of the Selling Stockholders may from time to time make gifts of any or
all of his shares as collateral for loans. In the event of such gift or of a
default under any such loan, the donee may elect to sell donated shares or the
lender may elect to sell shares held as collateral by means of the prospectus as
supplemented.
