Notice of Additional Disclosure and Partial Amendment to Notice Regarding the Commencement of a Tender Offer of the Shares, etc. of CSK Corporation"(91KB/PDF)

[Translation]

March 9, 2011

To whom it may concern,

Company Name Sumitomo Corporation
President Name Susumu Kato
President and CEO
(Code: 8053, First Section of Tokyo Stock
Exchange)
Inquiries Kazuho Enaka
Deputy General Manager
Corporate Communications Dept.
(TEL．+81-3-5166-3100）

Company Name Sumisho Computer Systems Corporation
President Name Nobuhide Nakaido
Chairman and CEO
(Code: 9719, First Section of Tokyo Stock
Exchange)
Inquiries Nobuhiro Mitsuishi General Manager,
Corporate Communications & Investor
Relations Div.
(TEL. +81-3-5166-1150)

Notice of Additional Disclosure and Partial Amendment to
“Notice Regarding the Commencement of a Tender Offer of the Shares, etc. of CSK Corporation”

Sumitomo Corporation (“Sumitomo”) and Sumisho Computer Systems Corporation (“SCS”;
Sumitomo and SCS are collectively referred to as the “Tender Offerors”) announced in their press
release dated February 24, 2011, titled “Notice Regarding the Commencement of a Tender Offer of the
Shares, etc. of CSK Corporation” that they will acquire Shares, etc. of CSK Corporation (Code: 9737;
First Section of Tokyo Stock Exchange; “CSK” or the “Target Company”) through a tender offer (the
“Tender Offer”). The Tender Offerors hereby announce that they have determined to commence the
Tender Offer from March 10, 2011, as scheduled.

In addition, the Tender Offerors hereby amend the content of the above-mentioned “Notice
Regarding the Commencement of a Tender Offer of the Shares, etc. of CSK Corporation” as below, in
accordance with the commencement of the Tender Offer from March 10, 2011, as mentioned above, the
determining of the “Number of Voting Rights Represented by Shares, etc. Held by Special Related
Parties before the Tender Offer,” which was announced as “unknown” in “2. Outline of the Tender
Offer” - “(6) Change in Ownership Percentage of Shares, etc. as a result of the Tender Offer” of the
above-mentioned “Notice Regarding the Commencement of a Tender Offer of the Shares, etc. of CSK
Corporation” and the matters which have occurred in connection with the Tender Offer on or after
February 24, 2011:

The amended portions of the press release have been underlined below. “The date hereof”
referred to in “2. Outline of the Tender Offer” - “(6) Change in Ownership Percentage of Shares, etc. as a
result of the Tender Offer” before the determining of the “Number of Voting Rights Represented by
Shares, etc. Held by Special Related Parties before the Tender Offer” means February 24, 2011.

To continue reading, please go to the following page:
http://www.sumitomocorp.co.jp/english/news/pdf/td110309e.pdf