
<PAGE>   1


                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                   FORM 8-A/A


                FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES
                    PURSUANT TO SECTION 12(b) OR 12(g) OF THE
                         SECURITIES EXCHANGE ACT OF 1934



                                  CLARCOR INC.
             (Exact name of registrant as specified in its charter)


       Delaware                                        36-0922490
  (State of incorporation                            (I.R.S. Employer
  or organization)                                  Identification No.)


           2323 Sixth Street, P.O. Box 7007, Rockford, Illinois 61125
           ----------------------------------------------------------
              (Address of principal executives offices) (Zip Code)


If this Form relates to                          If this Form relates to
the registration of a                            the registration of a
class of securities                              class of securities
pursuant to Section 12(b)                        pursuant to Section 12(g)
of the Exchange Act and                          of the Exchange Act and
is effective upon filing                         is effective pursuant to
pursuant to General                              General Instruction A(d),
Instruction A(c), please                         please check the
check the following box.                         following box.
[ ]                                              [ ]


Securities Act registration statement                             N/A
file to which this form relates                             (If applicable)

Securities to be registered pursuant                     Name of Each Exchange
to Section 12(b) of the Act:                             on which Each Class
                                                         is to be Registered

Rights to Purchase Series              
B Junior Participating                                   New York Stock Exchange
Preferred Stock

                     Securities to be registered pursuant to
                            Section 12(g) of the Act:


                                      none
                                 --------------
                                 Title of Class
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Item 1. Description of Registrant's Securities to be Registered

                  This amendment to the Company's Registration Statement on Form
8-A is being filed for the purpose of amending the description of the Company's
Stockholder Rights Agreement as amended by the First Amendment dated as of March
23, 1999 thereto (the "First Amendment") which is filed as an Exhibit hereto.
The following amends and restates the summary of the rights to purchase shares
of Series B Junior Participating Preferred Stock of the Company. In all other
respects, the Description of the Registrant's Securities previously included in
the Company's Registration Statement on Form 8-A remains in effect.

SUMMARY OF RIGHTS TO PURCHASE SHARES OF SERIES B JUNIOR PARTICIPATING PREFERRED
STOCK

                  On March 28, 1996, the Board of Directors (the "Board") of
CLARCOR Inc., a Delaware corporation (the "Company"), declared a dividend of one
preferred stock purchase right (a "Right") for each outstanding share of Common
Stock, $1 par value (the "Common Stock"), of the Company. The dividend was paid
to holders of record of the Common Stock on April 25, 1996, (the "Record Date").
Each Right entitles the holder thereof (except as described below) to purchase
from the Company one one-hundredth of a share of the Series B Junior
Participating Preferred Stock, $100 par value (the "Preferred Shares"), of the
Company at a price (the "Exercise Price") of $80.00 per one one-hundredth of a
Preferred Share, subject to adjustment. The terms of the Rights are set forth in
the Stockholders Rights Agreement dated as of March 28, 1996, as amended (the
"Rights Agreement"), between the Company and First Chicago Trust Company of New
York, as Rights Agent (the "Rights Agent"). Capitalized terms not defined herein
have the respective meanings specified in the Rights Agreement.

DISTRIBUTION DATE; TRANSFER OF RIGHTS

                  Initially, the Rights associated with the Common Stock
outstanding as of the Record Date will be evidenced solely by the stock
certificates for such Common Stock, with a copy of this Summary of Rights
attached thereto. The Rights will separate from the Common Stock upon the
earlier to occur of (i) 10 Business Days after the first public announcement
that any Person (other than an Exempt Person (as hereinafter defined)) has
become an Acquiring Person (as hereinafter defined) and (ii) 10 Business Days
after the commencement by any Person (other than an Exempt Person) of,
or the first public announcement of its intention to commence, a tender or
exchange offer if, upon the consummation thereof, such Person would be the
Beneficial Owner of 15% or more of the outstanding shares of Common Stock (the
earliest of the dates specified in clauses (i) and (ii) being hereinafter called
the "Distribution Date"). After the Distribution

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Date, the Rights will be evidenced solely by separate certificates and will
trade independently from the Common Stock.

                  An "Acquiring Person" is any Person who or which, together
with its Affiliates and Associates, has acquired 15% or more of the shares of
Common Stock then outstanding, but does not include (i) the Company, (ii) any
Subsidiary of the Company, (iii) any employee benefit plan or other compensation
program or arrangement of the Company or of any such Subsidiary or (iv) any
Person holding shares of Common Stock for or pursuant to the terms of any such
plan, program or arrangement (the Persons specified in clauses (i) through (iv)
being herein collectively called "Exempt Persons"). A "Restricted Person" is an
Acquiring Person or any Affiliate or Associate thereof.

                  The Rights Agreement provides that, until the Distribution
Date (or the earlier redemption or expiration of the Rights), the Rights may be
transferred only with the associated shares of Common Stock. Until the
Distribution Date (or the earlier redemption or expiration of the Rights), stock
certificates for Common Stock issued after the Record Date, either upon transfer
of outstanding shares or original issuance of additional shares of Common Stock,
will contain a legend incorporating the Rights Agreement by reference. Until the
Distribution Date (or the earlier redemption or expiration of the Rights), the
surrender for transfer of any stock certificate for shares of Common Stock, with
or without such legend and whether or not a copy of this Summary of Rights is
attached thereto, will also constitute the transfer of the Rights associated
with the shares of Common Stock represented by such stock certificate.

                  As soon as practicable after the Distribution Date, separate
certificates evidencing the Rights ("Rights Certificates") will be mailed to the
holders of record of the Common Stock as of the Close of Business on the
Distribution Date, which thereafter will constitute the sole evidence of the
Rights. Each share of Common Stock issued by the Company after the Record Date
and prior to the earlier redemption or expiration of the Rights, including any
shares of Common Stock issued by reason of the exercise of any option, warrant,
right (other than the Rights) or conversion or exchange privilege (however
evidenced) issued by the Company prior to the Distribution Date, will be
accompanied by a Right (unless the Board expressly provides to the contrary at
the time of issuance of any such option, warrant, right or privilege), and
Rights Certificates evidencing such Rights will be issued at the same time as
the stock certificates for the associated shares of Common Stock.

                  The Rights are not exercisable until the Distribution Date.
Moreover, the time when the Rights may be exercised is restricted as described
in the next paragraph. The Rights will expire on April 25, 2006 (the "Final
Expiration Date"), unless the Final Expiration Date is extended or unless the
Rights are earlier

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redeemed or exchanged by the Company, in each case as described below.

EXERCISE OF RIGHTS UNDER CERTAIN CIRCUMSTANCES

                  In the event that any Person becomes an Acquiring Person,
proper provision will be made so that the registered holder of each Right (other
than Rights Beneficially Owned as described in the next sentence) will
thereafter have the right to receive, upon exercise thereof, the number of
shares of Common Stock which, at the time of the occurrence of such event, will
have a market value equal to two times the then current Exercise Price. After
any Person becomes an Acquiring Person, all Rights which are, or (under certain
circumstances specified in the Rights Agreement) were, Beneficially Owned by a
Restricted Person or specified transferees therefrom will be or become void.

                  If, on or after the date on which any Person has become an
Acquiring Person, any of the following transactions occur: (i) the Company
merges into or consolidates with an Interested Stockholder (as hereinafter
defined) or, unless all holders of the Company's outstanding shares of Common
Stock are treated the same, another Person (with limited designated exceptions);
(ii) an Interested Stockholder or, unless all holders of the Company's
outstanding shares of Common Stock are treated the same, another Person (with
limited designated exceptions) merges into the Company and either (A) all or
part of the outstanding shares of Common Stock of the Company are converted into
capital stock or other securities of any other Person (or the Company), cash
and/or other property or (B) such shares remain outstanding, unconverted and
unchanged; or (iii) the Company sells or transfers 50% or more of its
consolidated assets or earning power to an Interested Stockholder (as
hereinafter defined) or, unless all holders of the Company's outstanding shares
of Common Stock are treated the same, another Person (with limited designated
exceptions); proper provision will be made so that the registered holder of each
Right (other than Rights which have become void) will thereafter have the right
(the "Flip-Over Right") to receive, upon exercise thereof, the number of common
shares of the acquiror (or of another Person affiliated therewith) which, at the
time of consummation of such transaction, will have a market value equal to two
times the then current Exercise Price. An "Interested Stockholder" is any
Restricted Person or any Affiliate or Associate of any other Person in which
such Restricted Person has an interest, or any Person acting, directly or
indirectly, on behalf of or in concert with any such Restricted Person.

ADJUSTMENTS TO EXERCISE PRICE AND STOCK PURCHASABLE UPON EXERCISE

                  The Exercise Price payable, the number and kind of shares of
capital stock issuable upon exercise of the Rights and the number of Rights
outstanding are subject to adjustment from time to time to prevent dilution (i)
in the event of a dividend payable in

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Preferred Shares on, or a subdivision, combination or reclassification of, the
Preferred Shares, (ii) upon the grant to the holders of the Preferred Shares of
certain options, warrants or rights to subscribe for or purchase Preferred
Shares at a price, or securities convertible into or exchangeable for Preferred
Shares with a conversion or exchange price, less than the then Fair Market Value
of the Preferred Shares or (iii) upon the distribution to the holders of the
Preferred Shares of cash, securities, evidences of indebtedness or other
property (other than a regular quarterly cash dividend or a dividend payable in
Preferred Shares) or options, warrants or rights (other than those referred to
in clause (ii) above).

                  The number of outstanding Rights and the number of one
one-hundredths of a Preferred Share issuable upon exercise of each Right are
also subject to adjustment in the event of a dividend on the Common Stock
payable in shares of Common Stock or a subdivision, combination or
reclassification of the Common Stock occurring, in any such case, prior to the
Distribution Date.

                  With certain specified exceptions, no adjustment in the
Exercise Price will be made until the cumulative adjustments required equal at
least 1% of the Exercise Price. The Company is not required to issue fractional
Preferred Shares (other than fractions which are multiples of one one-hundredth
of a Preferred Share), but in lieu thereof the Company would be required to make
a cash payment based on the Fair Market Value of the Preferred Shares on the
trading day immediately preceding the date of exercise.

TERMS OF PREFERRED SHARES

                  The Preferred Shares receivable upon exercise of the Rights
will not be redeemable. Each Preferred Share will entitle the holder thereof to
receive a preferential quarterly dividend equal to the greater of (i) $64 and
(ii) 100 times the aggregate per share amount of all cash dividends, plus 100
times the aggregate per share amount (payable in kind) of all non-cash dividends
and other distributions (other than in shares of Common Stock), declared on the
Common Stock during such quarter, adjusted to give effect to any dividend on the
Common Stock payable in shares of Common Stock or any subdivision, combination
or reclassification of the Common Stock (a "Dilution Event"). Each Preferred
Share will entitle the holder thereof to 100 votes on all matters submitted to a
vote of the stockholders of the Company, voting together as a single class with
the holders of the Common Stock and the holders of any other class of capital
stock having general voting rights, adjusted to give effect to any Dilution
Event. In the event of liquidation of the Company, the holder of each Preferred
Share will be entitled to receive a preferential liquidation payment equal to
(i) the greater of $100 or (ii) 100 times the aggregate per share amount to be
distributed to the holders of the Common Stock, adjusted to give effect to any

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Dilution Event, plus an amount equal to accrued and unpaid dividends and
distributions on such Preferred Share, whether or not declared, to the date of
such payment. In the event of any merger, consolidation or other transaction in
which the outstanding shares of Common Stock of the Company are exchanged for or
converted into other capital stock, securities, cash and/or other property, each
Preferred Share will be similarly exchanged or converted into 100 times the per
share amount applicable to the Common Stock, adjusted to give effect to any
Dilution Event.

                  Because of the nature of the dividend, voting, liquidation and
other rights accorded to each Preferred Share, the value of the one
one-hundredth of a Preferred Share receivable upon the exercise of each Right
should approximate the value of one share of Common Stock.

REDEMPTION OF RIGHTS

                  At any time prior to the earliest of (i) 10 Business Days
after the first public announcement that any Person (other than an Exempt
Person) has become an Acquiring Person, (ii) the occurrence of any transaction
which permits the exercise of the Flip-Over Right and (iii) the Final Expiration
Date, the Board may redeem the Rights in whole, but not in part, at the
redemption price of $.01 per Right, adjusted to give effect to any Dilution
Event (the "Redemption Price"). The redemption of the Rights may be made
effective at such time, on such basis and with such conditions as the Board, in
its sole discretion, may establish. After the redemption period has expired, the
Company's right of redemption may be reinstated, under the circumstances
specified in the Rights Agreement, if either (i) the Person who became an
Acquiring Person shall reduce, in one or a series of related transactions not
involving the Company or any Subsidiary or the occurrence of any transaction
which permits the exercise of the Flip-Over Right, its Beneficial Ownership of
the outstanding shares of Common Stock to less than 15% of such outstanding
shares or (ii) in connection with any transaction which permits the exercise of
the Flip-Over Right, which does not involve an Interested Stockholder and in
which all holders of the Common Stock are treated the same. Immediately after
action by the Board directing the redemption of the Rights, the option to
exercise the Rights will terminate, and thereafter each registered holder of the
Rights will only be entitled to receive the Redemption Price therefor.

EXCHANGE OF RIGHTS

                  At any time after any Person has become an Acquiring Person
and prior to the time that any Person (other than an Exempt Person), together
with its Affiliates and Associates, has become the Beneficial Owner of 50% or
more of the outstanding shares of Common Stock, the Board may direct that all or
any part of the outstanding Rights (other than Rights which have become void) be
exchanged for shares of Common Stock at the exchange rate of one

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share of Common Stock per Right, adjusted to give effect to any Dilution Event.

AMENDMENT OF THE RIGHTS AND THE RIGHTS AGREEMENT

                  Prior to the Distribution Date, the terms of the Rights and
the Rights Agreement may be supplemented or amended by the Board in any manner.
From and after the Distribution Date, the Rights may be supplemented or amended
by the Board, without the approval of the holders of the Rights, in certain
respects which do not adversely affect, as determined by the Board, the
interests of such holders; provided, however, that the Rights Agreement cannot
be amended to lengthen (i) any time period unless such lengthening is for the
benefit of the holders of the Rights or (ii) any time period relating to when
the Rights may be redeemed if at such time the Rights are not then redeemable.

MISCELLANEOUS

                  Until a Right is exercised, the holder thereof, as such, will
have no rights as a stockholder of the Company, including, without limitation,
the right to vote or to receive dividends.

                  A copy of the Rights Agreement, as amended, is available free
of charge from the Company. This summary description of the Rights does not
purport to be complete and is qualified in its entirety by reference to the
Rights Agreement and to the First Amendment, both of which are hereby
incorporated herein by reference.



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Item 2.           Exhibits

Exhibit No.                                          Description

         1.                The registrant's Second Restated Certificate of
                           Incorporation is hereby incorporated by reference to
                           Exhibit 3.1 to the registrant's Annual Report on Form
                           10-K for the fiscal year ended November 30, 1998
                           (File No. 1-11024).

         2.                The registrant's By-Laws, as amended, are hereby
                           incorporated by reference to Exhibit 3.2 to the
                           registrant's Annual Report on Form 10-K for the
                           fiscal year ended November 30, 1995 (File No. 1-
                           11024).

         3.                Stockholders Rights Agreement dated as of March 28,
                           1996 between the registrant and First Chicago Trust
                           Company of New York is hereby incorporated by
                           reference to Exhibit 4 to the registrant's Current
                           Report on Form 8-K filed April 3, 1996.

         4.                First Amendment to Stockholders Rights Agreement
                           dated as of March 23, 1999. (filed herewith)


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                                    SIGNATURE


                  Pursuant to the requirements of Section 12 of the Securities
Exchange Act of 1934, the registrant has duly caused this registration statement
to be signed on its behalf by the undersigned, thereunto duly authorized.

Date:  March 29, 1999




                                       CLARCOR INC.



                                       By:       /s/ Lawrence E. Gloyd
                                                --------------------------------
                                                Name:  Lawrence E. Gloyd
                                                Title:  Chairman

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                                  EXHIBIT INDEX


Exhibit No.                                          Description
-----------                                          -----------

         1.                The registrant's Second Restated Certificate of
                           Incorporation is hereby incorporated by reference to
                           Exhibit 3.1 to the registrant's Annual Report on Form
                           10-K for the fiscal year ended November 30, 1998
                           (File No. 1-11024).

         2.                The registrant's By-Laws, as amended, are hereby
                           incorporated by reference to Exhibit 3.2 to the
                           registrant's Annual Report on Form 10-K for the
                           fiscal year ended November 30, 1995 (File No. 1-
                           11024).

         3.                Stockholders Rights Agreement dated as of March 28,
                           1996 between the registrant and First Chicago Trust
                           Company of New York is hereby incorporated by
                           reference to Exhibit 4 to the registrant's Current
                           Report on Form 8-K filed April 3, 1996.

         4.                First Amendment to Stockholders Rights Agreement
                           dated as of March 23, 1999. (filed herewith)



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