UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 8-K

CURRENT REPORT
Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): June 2, 2009

Tesoro Corporation

(Exact name of registrant as specified in its charter)

Delaware	1-3473	95-0862768
(State or other jurisdiction	(Commission File Number)	(IRS Employer Identification No.)
of incorporation)

300 Concord Plaza Drive
San Antonio, Texas	78216-6999
(Address of principal executive offices)	(Zip Code)

(210) 828-8484
(Registrant’s telephone number,
including area code)

Not Applicable
(Former name or former address, if
changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2.):

o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 8.01 Other Events.

On June 2, 2009, Tesoro Corporation issued a press release announcing that it is proposing to offer in a registered offering $300 million of senior unsecured notes due 2019, subject to market conditions. Net proceeds from the offering will be used for general corporate purposes, including the repayment or the refinancing of indebtedness, capital expenditures and working capital. The press release is filed as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference.

9.01 Financial Statements and Exhibits.

(d) Exhibits.

99.1 Press release issued on June 2, 2009.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934 the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: June 2, 2009

TESORO CORPORATION
By:	/s/ GREGORY A. WRIGHT
	Gregory A. Wright
	Executive Vice President and Chief Financial Officer

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Index to Exhibits

Exhibit Number	Description
99.1	Press release issued on June 2, 2009.

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