<PAGE>
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SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
------------------------
SCHEDULE 14D-1/A
TENDER OFFER STATEMENT PURSUANT TO SECTION 14(d)(1)
OF THE
SECURITIES EXCHANGE ACT OF 1934
(AMENDMENT NO. 1)
AND
SCHEDULE 13D/A
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(AMENDMENT NO. 1)
------------------------
ENDOGEN, INC.
(Name of Subject Company)
EWOK ACQUISITION CORP.
PERBIO SCIENCE AB
PERSTORP AB
(Bidders)
COMMON STOCK, PAR VALUE $0.01
(Title of Class of Securities)
29264J 10 8
(CUSIP Number of Class of Securities)
MAGNUS LINDQUIST
CHIEF FINANCIAL OFFICER
PERSTORP AB
SE-284 80 PERSTORP, SWEDEN
011-46-435-380-00
------------------------
COPIES TO:
PATRICIA KAVEE MELICK, ESQ.
WIGGIN & DANA
THREE STAMFORD PLAZA
STAMFORD, CONNECTICUT 06911
(203) 363-7600
(Name, Address and Telephone Number of Persons Authorized to
Receive Notices and Communications on Behalf of Bidders)
MAY 27, 1999
(Date of Event which Requires Filing Statement on Schedule 13D)
------------------------
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<PAGE>
<TABLE>
<S> <C> <C> <C>
1 NAMES OF REPORTING PERSONS
IRS IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)
Ewok Acquisition Corp.
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [x]
(b) [ ]
3. SEC USE ONLY
4. SOURCE OF FUNDS*
AF
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT
TO ITEM 2(e) or 2(f) [ ]
6. CITIZENSHIP OR PLACE OF ORGANIZATION
Massachusetts
NUMBER OF 7. SOLE VOTING POWER 0
SHARES
BENEFICIALLY 8. SHARED VOTING POWER 1,259,772
OWNED BY
EACH 9. SOLE DISPOSITIVE POWER 0
REPORTING
PERSON WITH 10. SHARED DISPOSITIVE POWER 1,259,772
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,259,772
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES* [ ]
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
30.3%
14. TYPE OF REPORTING PERSON*
CO
</TABLE>
*SEE INSTRUCTIONS BEFORE FILLING OUT!
2
<PAGE>
<TABLE>
<S> <C> <C> <C>
1 NAMES OF REPORTING PERSONS
IRS IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)
PerBio Science AB
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [x]
(b) [ ]
3. SEC USE ONLY
4. SOURCE OF FUNDS*
AF
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT
TO ITEM 2(e) or 2(f) [ ]
6. CITIZENSHIP OR PLACE OF ORGANIZATION
Sweden
NUMBER OF 7. SOLE VOTING POWER 0
SHARES
BENEFICIALLY 8. SHARED VOTING POWER 1,259,772
OWNED BY
EACH 9. SOLE DISPOSITIVE POWER 0
REPORTING
PERSON WITH 10. SHARED DISPOSITIVE POWER 1,259,772
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,259,772
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES* [ ]
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
30.3%
14. TYPE OF REPORTING PERSON*
CO
</TABLE>
*SEE INSTRUCTIONS BEFORE FILLING OUT!
3
<PAGE>
<TABLE>
<S> <C> <C> <C>
1 NAMES OF REPORTING PERSONS
IRS IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)
Perstorp AB
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [x]
(b) [ ]
3. SEC USE ONLY
4. SOURCE OF FUNDS*
WC
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT
TO ITEM 2(e) or 2(f) [ ]
6. CITIZENSHIP OR PLACE OF ORGANIZATION
Sweden
NUMBER OF 7. SOLE VOTING POWER 0
SHARES
BENEFICIALLY 8. SHARED VOTING POWER 1,259,772
OWNED BY
EACH 9. SOLE DISPOSITIVE POWER 0
REPORTING
PERSON WITH 10. SHARED DISPOSITIVE POWER 1,259,772
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,259,772
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES* [ ]
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
30.3%
14. TYPE OF REPORTING PERSON*
CO
</TABLE>
*SEE INSTRUCTIONS BEFORE FILLING OUT!
4
<PAGE>
EXPLANATORY NOTE
This Amendment No. 1 to Tender Offer Statement on Schedule 14D-1/A and
Amendment No. 1 to Schedule 13D on Schedule 13D/A (collectively, along with the
original Schedule 14D-1 and Schedule 13D, dated and filed with the Securities
and Exchange Commission on June 2, 1999, the 'Schedule 14D-1') relates to the
offer by Ewok Acquisition Corp, a Massachusetts corporation ('Purchaser') and a
wholly-owned subsidiary of PerBio Science AB, a Swedish corporation ('Parent'),
which is a direct wholly-owned subsidiary of Perstorp AB, a Swedish corporation
('Perstorp'), to purchase all outstanding shares of common stock, $.01 par value
per share (the 'Shares'), of Endogen, Inc., a Massachusetts corporation (the
'Company'), at a price of $3.75 per Share, net to the seller in cash, upon the
terms and subject to the conditions set forth in the Purchaser's Offer to
Purchase, dated June 2, 1999 (the 'Offer to Purchase'), as supplemented by the
Supplement to Offer to Purchase, dated June 17, 1999 (the 'Supplement'), and in
the related Letter of Transmittal, copies of which have been attached to the
Schedule 14D-1 as Exhibits (a)(1), (a)(10) and (a)(2), respectively.
Capitalized terms used, but not otherwise defined, herein have the meanings
ascribed to such terms in the Offer to Purchase, as amended by the Supplement.
ITEM 3. PAST CONTACTS, TRANSACTIONS OR NEGOTIATIONS WITH THE SUBJECT COMPANY.
(a) and (b) The information set forth in Section 10 'Background of the
Offer; Contacts with the Company' and Section 11 'Purpose of the Offer and the
Merger; Plans for the Company; Appraisal Rights' of the Offer to Purchase, as
supplemented by the Supplement is incorporated herein by reference.
ITEM 7. CONTRACTS, ARRANGEMENTS, UNDERSTANDINGS OR RELATIONSHIPS WITH RESPECT TO
THE SUBJECT COMPANY'S SECURITIES.
The information set forth in 'Introduction,' Section 9 'Certain Information
Concerning Perstorp, the Purchaser and Parent,' Section 10 'Background of the
Offer; Contacts with the Company,' Section 11 'Purpose of the Offer and the
Merger; Plans for the Company; Appraisal Rights,' Section 12 'The Merger
Agreement; Stockholder Agreement; Employment Agreements and Confidentiality
Agreement,' and Section 13 'Source and Amount of Funds' of the Offer to
Purchase, as supplemented by the Supplement is incorporated herein by reference.
ITEM 10. ADDITIONAL INFORMATION.
(f) The information set forth in the Offer to Purchase, the Supplement, the
Letter of Transmittal, the Agreement and Plan of Merger dated as of May 27, 1999
and related Letter Agreement, among the Purchaser, Parent and the Company, the
Stockholder Agreement the Employment Agreements, copies of which are attached
hereto as Exhibits (a)(1), (a)(10), (a)(2), (c)(1), (c)(2), (c)(3) and (c)(4),
respectively, is incorporated herein by reference.
ITEM 11. MATERIAL TO BE FILED AS EXHIBITS.
Item 11 of Schedule 14D-1 is hereby amended to add the following exhibit:
(a)(10) -- Supplement to Offer to Purchase, dated June 17, 1999.
5
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SIGNATURES
After due 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 17, 1999
EWOK ACQUISITION CORP.
By: /s/ ROBB ANDERSON
....................................
NAME: ROBB ANDERSON
TITLE: PRESIDENT
PERBIO SCIENCE AB
By: /s/ MATS FISCHIER
....................................
NAME: MATS FISCHIER
TITLE: DIRECTOR
PERSTORP AB
By: /s/ AKE FREDRIKSSON
....................................
NAME: AKE FREDRIKSSON
TITLE: PRESIDENT AND CHIEF EXECUTIVE
OFFICER
6
<PAGE>
EXHIBIT INDEX
<TABLE>
<CAPTION>
EXHIBIT
NUMBER DESCRIPTION
- --------- ---------------------------------------------------------
<S> <C>
(a) (10) -- Supplement to Offer to Purchase, dated June 17, 1999.
</TABLE>
<PAGE>
SUPPLEMENT
TO
OFFER TO PURCHASE
ALL OUTSTANDING SHARES OF COMMON STOCK
OF
ENDOGEN, INC.
AT
$3.75 NET PER SHARE IN CASH
BY
EWOK ACQUISITION CORP.
A WHOLLY-OWNED SUBSIDIARY
OF
PERBIO SCIENCE AB
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THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY
TIME, ON TUESDAY, JUNE 29, 1999, UNLESS THE OFFER IS EXTENDED.
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THIS SUPPLEMENT, DATED JUNE 17, 1999, SUPPLEMENTS AND AMENDS THE OFFER
TO PURCHASE, DATED JUNE 2, 1999, RELATING TO THE PROPOSED OFFER TO PURCHASE ALL
OUTSTANDING SHARES OF COMMON STOCK OF ENDOGEN, INC. (THE "OFFER TO PURCHASE").
THIS SUPPLEMENT, WHICH SHOULD BE READ IN CONJUNCTION WITH THE OFFER TO PURCHASE,
IS BEING PROVIDED TO GIVE YOU CERTAIN ADDITIONAL INFORMATION. THE TERMS OF THE
OFFER HAVE NOT BEEN CHANGED AND YOU MAY CONTINUE TO USE THE LETTER OF
TRANSMITTAL AND PROCEDURES FOR TENDERING PREVIOUSLY DELIVERED TO YOU.
CAPITALIZED TERMS USED HEREIN AND NOT OTHERWISE DEFINED HAVE THE MEANINGS
ASCRIBED TO THEM IN THE OFFER TO PURCHASE.
The Dealer Manager for the Offer is:
VECTOR SECURITIES INTERNATIONAL, INC.
June 17, 1999
<PAGE>
TO ALL HOLDERS OF COMMON STOCK OF ENDOGEN, INC.:
8. CERTAIN INFORMATION CONCERNING THE COMPANY
THE COMPANY PROVIDED TO PARENT AND PURCHASER CERTAIN PROJECTIONS
RELATING TO THE OPERATIONS OF THE COMPANY. THE FOLLOWING PARAGRAPHS ARE
INSERTED IMMEDIATELY PRIOR TO THE LAST PARAGRAPH OF SECTION 8 OF THE OFFER TO
PURCHASE:
During the course of discussions among Parent, Purchaser and the
Company, the Company provided Purchaser and Parent certain non-public
consolidated financial projections (the "Projections") relating to the
operations of the Company, which are summarized below. The Projections were not
prepared by the Company with a view to public disclosure or compliance with the
published guidelines of the Commission regarding projections or with the
guidelines established by the American Institute of Certified Public
Accountants and are included in this Offer to Purchase only because they were
furnished to Parent and Purchaser. The Company has advised Purchaser and Parent
that its internal financial forecasts (upon which the Projections provided to
Parent were based) are, in general, prepared solely for internal use and capital
budgeting and other management decisions, are based upon a variety of estimates
and hypothetical assumptions, which may not be accurate or realized, and are
subjective in many respects and thus susceptible to interpretations and periodic
revisions based on actual experience and business development. The Projections
are "forward-looking" and inherently subject to significant uncertainties and
contingencies, many of which are beyond the control of the Company, including
industry performance, general business and economic conditions, changing
competition, adverse changes in applicable laws, regulations or rules governing
life science companies, tax, accounting and other matters. Accordingly, it is
expected that there will be differences between actual and projected results,
and actual results may be materially higher or lower than those projected. The
inclusion of this information should not be regarded as an indication that
Parent, Purchaser, the Company, their respective financial advisors or anyone
who received this information considered it a reliable predictor of future
events and this information should not be relied on as such. Parent conducted an
independent assessment of the Company's value and did not rely to any material
degree on the Projections. None of Parent, Purchaser, the Company or their
respective financial advisors assumes any responsibility for the validity,
reasonableness, accuracy or completeness of the Projections and the Company has
made no representation to Parent or Purchaser regarding the Projections.
The Projections indicated that (a) revenues for the fiscal years ending
May 31, 1999, 2000 and 2001 were estimated to be $10,296,281, $13,060,490 and
$16,043,754, respectively; (b) cost of revenues for the fiscal years ending May
31, 1999, 2000 and 2001 was estimated to be $3,871,949, $4,560,000 and
$5,545,000, respectively; (c) selling, general and administrative expenses for
the fiscal years ending May 31, 1999, 2000 and 2001 were estimated to be
$4,566,279, $5,120,000 and $5,690,000, respectively; (d) research and
development expenses for the fiscal years ending May 31, 1999, 2000 and 2001
were estimated to be $2,054,333, $2,460,000 and $2,685,000, respectively; (e)
interest income, net for the fiscal years ending May 31, 1999, 2000 and 2001
was estimated to be $2,750, $25,000 and $55,000, respectively; (f) loss
before taxes for the fiscal year ending May 31, 1999 was estimated to be
$193,530 and income before income taxes for the fiscal years ending May 31,
2000 and 2001 was estimated to be $945,490 and $2,178,754, respectively;
(g) income tax provision for the fiscal years ending May 31, 1999, 2000 and 2001
was estimated to be $0, $397,106 and $915,077, respectively; and (h) net loss
for the fiscal year ending May 31, 1999 was estimated to be $193,530 and net
income for the fiscal years ending May 31, 2000 and 2001 was estimated
to be $548,384 and $1,263,677, respectively.
2
<PAGE>
10. BACKGROUND OF THE OFFER; CONTACTS WITH THE COMPANY
THE THIRD PARAGRAPH OF SECTION 10 OF THE OFFER TO PURCHASE IS AMENDED
TO ADD THE FOLLOWING SENTENCE TO THE END OF THAT PARAGRAPH:
See Section 8 "Certain Information Concerning the Company" for
disclosure regarding certain projections that were delivered to Parent and
Purchaser.
<PAGE>
Any questions or requests for assistance may be directed to the
Information Agent or the Dealer Manager at their respective addresses and
telephone numbers set forth below. Additional copies of this Supplement, the
Offer to Purchase, the Letter of Transmittal and the Notice of Guaranteed
Delivery may be obtained from the Information Agent. Stockholders may also
contact their local broker, dealer, commercial bank, trust company or other
nominee for assistance concerning the Offer.
The Information Agent for the Offer is:
GEORGESON
& COMPANY INC.
Wall Street Plaza
New York, NY 10005
(212) 440-9800 (Collect)
or Call Toll Free (800) 223-2064
The Dealer Manager for the Offer is:
Vector Securities International, Inc.
1751 Lake Cook Road
Suite 350
Deerfield, IL 60015
(847) 374-3853 (Collect)
