ABBOTT LABORATORIES — Regulatory Filings 2003

Dec 15, 2003

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SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549

SCHEDULE TO (Rule 14d-100) Tender Offer Statement Under Section 14(d)(1) or Section 13(e)(1) of the Securities Exchange Act of 1934

i-STAT CORPORATION (Name of Subject Company (Issuer))

Senator Acquisition Corporation a wholly owned subsidiary of ABBOTT LABORATORIES (Names of Filing Persons (Offerors))

Common Stock, Par Value $.15 Per Share (Title of Class of Securities)

450213 10 3 (CUSIP Number of Class of Securities)

Jose M. de Lasa Senior Vice President and General Counsel Abbott Laboratories 100 Abbott Park Road Abbott Park, Illinois 60064-6400 (847) 937-6100 (Name, address and telephone number of person authorized to receive notices and communications on behalf of filing persons)

Copy to: James T. Lidbury Mayer, Brown, Rowe & Maw LLP 190 South LaSalle Street Chicago, Illinois 60603 Telephone: (312) 782-0600

CALCULATION OF FILING FEE

User-specified TAGGED TABLE

Transaction Valuation*	Amount of Filing Fee
Not Applicable	Not Applicable

end of user-specified TAGGED TABLE o Check the box if any part of the fee is offset as provided by Rule 0-11(a)(2) and identify the filing with which the offsetting fee was previously paid. Identify the previous filing by registration statement number or the Form or Schedule and the date of its filing. User-specified TAGGED TABLE

Amount Previously Paid:	Filing Party:
Form or Registration No.:	Date Filed:

end of user-specified TAGGED TABLE ý Check the box if the filing relates solely to preliminary communications made before the commencement of a tender offer.

Check the following box if the filing is a final amendment reporting the results of the tender offer. o

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Item 12. Exhibits

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