<PAGE>
Prospectus Supplement No. 6 Filed Pursuant to Rule 424(b)(3)
dated June 5, 2000 Registration No. 333-30540
(to Prospectus dated April 24, 2000) Cusip No. 501242AE1
$175,000,000
KULICKE AND SOFFA INDUSTRIES, INC.
4 3/4% Convertible Subordinated Notes due 2006 and
the Common Stock Issuable upon Conversion of the Notes
-----------------------
The following table supplements and amends the information set forth on
pages 30 to 33 in the prospectus under Selling Securityholders with respect to
the selling securityholders and the principal amount of notes beneficially owned
by such selling securityholders that may be offered and sold pursuant to the
prospectus dated April 24, 2000. This prospectus supplement is not complete
without, and may not be delivered or utilized except in connection with, the
prospectus.
<TABLE>
<CAPTION>
Principal Amount Number of Number of
at Maturity of Shares of Shares of
Notes Beneficially Percentage Common Stock Common Stock Percentage of
Owned that May of Notes Owned Prior that May Common Stock
Name Be Sold Outstanding to the Offering Be Sold (1) Outstanding (2)
---------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C>
Bankers Trust Trustee $915,000 * 19,978 19,978 *
For Daimler Chrysler
Corp. Employee #1
Pension Plan
---------------------------------------------------------------------------------------------------------------------------
State Street Bank 450,000 * 9,825 9,825 *
Custodian For GE
Pension Trust
---------------------------------------------------------------------------------------------------------------------------
Franklin and Marshall 60,000 * 1,310 1,310 *
College
---------------------------------------------------------------------------------------------------------------------------
Penn Treaty Network 75,000 * 1,638 1,638 *
America Insurance
Company
---------------------------------------------------------------------------------------------------------------------------
The Estate of James 636,000 * 13,887 13,887 *
Campbell
---------------------------------------------------------------------------------------------------------------------------
Amoco Corporation 1,592,000 * 34,760 34,760 *
Master Trust
---------------------------------------------------------------------------------------------------------------------------
PGEP IV, LLC 140,000 * 3,057 3,057 *
---------------------------------------------------------------------------------------------------------------------------
Jefferies & Co. Inc 13,000 * 284 284 *
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</TABLE>
<PAGE>
<TABLE>
<CAPTION>
Principal Amount Number of Number of
at Maturity of Shares of Shares of
Notes Beneficially Percentage Common Stock Common Stock Percentage of
Owned that May of Notes Owned Prior that May Common Stock
Name Be Sold Outstanding to the Offering Be Sold (1) Outstanding (2)
---------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C>
Tracor Inc. Employees 207,000 * 4,520 4,520 *
Retirement Plan
---------------------------------------------------------------------------------------------------------------------------
Viacom Pension Plan 83,000 * 1,812 1,812 *
Master Trust
---------------------------------------------------------------------------------------------------------------------------
Hotel Union and Hotel 578,000 * 12,620 12,620 *
Industry of Hawaii
---------------------------------------------------------------------------------------------------------------------------
ITG Inc. 132,000 * 2,882 2,882 *
---------------------------------------------------------------------------------------------------------------------------
Minnesota Bakers Union 62,000 * 1,354 1,354 *
Pension Fund
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</TABLE>
* Less than 1%
(1) Assumes conversion of all of the holder's notes at a conversion price of
$45.7993 per share of common stock. However, this conversion price will be
subject to adjustment as described under "Description of Notes-Conversion
of Notes." As a result, the amount of common stock issuable upon
conversion of the notes may increase or decrease in the future.
(2) Calculated based on Rule 13d-3(d)(i) of the Exchange Act using 24,020,358
shares of common stock outstanding as of April 14, 2000. In calculating
this amount, we treated as outstanding the number of shares of common stock
issuable upon conversion of all of that particular holder's notes.
However, we did not assume the conversion of any other holder's notes.
Because the selling securityholders listed above and in the prospectus
under the caption Selling Securityholders may, pursuant to the prospectus, as
supplemented, offer all or some portion of the notes, no estimate can be given
as to the amount of notes that will be held by the selling securityholders upon
termination of any such sales.
Furthermore, the selling securityholders identified in the table set forth
in the prospectus under the caption Selling Securityholders may have sold,
transferred or otherwise disposed of all or a portion of their notes or common
stock since the date on which they provided us with information regarding their
notes or common stock, and we have not made any independent inquiries as to the
foregoing.
Unless otherwise noted, all information provided in this prospectus
supplement is as of June 5, 2000.
