8-K

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): March 27, 2015

Tesoro Corporation

(Exact name of registrant as specified in its charter)

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

19100 Ridgewood Pkwy San Antonio, Texas	78259-1828
(Address of principal executive offices)	(Zip Code)

(210) 626-6000

(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 7.01 Regulation FD Disclosure.

Tesoro Corporation (the “Company”) issued a press release announcing that the Martinez, California refinery has begun the restart process and provide updates to the first quarter guidance. A copy of the press release is filed as Exhibit 99.1 to this Current Report on Form 8-K and incorporated herein by reference. Updates to the first quarter guidance is presented in the attached slides (the “Slide Presentation”) on March 27, 2015. The Slide Presentation is filed as Exhibit 99.2 to this Current Report on Form 8-K and is incorporated herein by reference.

The information above is being furnished, not filed, pursuant to Item 7.01 of Form 8-K. Accordingly, the information in Item 7.01 of this Current Report, including Exhibit 99.1 and Exhibit 99.2, will not be incorporated by reference into any registration statement filed by the Company under the Securities Act of 1933, as amended, unless specifically identified therein as being incorporated by reference.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits.
99.1	Press release of Tesoro issued on March 27, 2015.
99.2	Slide Presentation dated March 27, 2015.

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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: March 30, 2015

TESORO CORPORATION
By:	/s/ STEVEN M. STERIN
	Steven M. Sterin
	Executive Vice President and Chief Financial Officer

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Index to Exhibits

Exhibit Number	Description of the Exhibit
99.1	Press release of Tesoro issued on March 27, 2015.
99.2	Slide Presentation dated March 27, 2015.

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EX-99.1

Exhibit 99.1

Tesoro Corporation Begins Restart of Martinez Refinery and Updates First Quarter Guidance

SAN ANTONIO - March 27, 2015 - Tesoro Corporation (NYSE:TSO) today announced that the Martinez, California refinery has begun the restart process.

“We are pleased to have reached an agreement with the local union at our Martinez, California refinery and are commencing the restart process today,” said Greg Goff, Chairman and CEO. “The facility should be back to normal operating levels over the next two weeks.”

The Martinez, California refinery was in the final stages of major turnaround maintenance activity when the United Steelworkers Union (USW) issued a strike notice on February 1^st. The safest option at that time was to safely idle the remaining operating units and transition to operating the facility as a terminal.

Tesoro has also reached agreements with the local USW at its Carson, California and Anacortes, Washington refineries and employees at those refineries are returning to work. The local unions at the Mandan, North Dakota and Salt Lake City, Utah refineries are expected to vote on their respective contracts over the next few days.

For Tesoro, the strike resulted in higher operating costs than our previous guidance and lower capture rates compared to historical averages across our West Coast system. We currently estimate the California operating costs will be between $7.70 and $7.95 per barrel. The Martinez, California strike and Anacortes, Washington and Salt Lake City turnarounds will negatively impact system capture rates by approximately $1.50 to $2.00 per barrel during the first quarter, and we expect to realize a positive impact to capture rates in the second quarter as we complete the planned turnarounds.

The idling of operations at Martinez resulted in higher crude inventory along with the higher planned inventory ahead of the Anacortes, Washington and Salt Lake City, Utah refinery turnarounds, these inventory builds are expected to result in a use of working capital during the first quarter of 2015. We expect these working capital impacts will reverse in the second quarter, as we restart and come out of turnarounds at our refineries.

Tesoro Corporation, a Fortune 100 company, is an independent refiner and marketer of petroleum products. Tesoro, through its subsidiaries, operates six refineries in the western United States with a combined capacity of over 850,000 barrels per day and ownership in a logistics business which includes a 36% interest in Tesoro Logistics LP (NYSE: TLLP) and ownership of its general partner. Tesoro's retail-marketing system includes over 2,200 retail stations under the ARCO®, Shell®, Exxon®, Mobil®, USA Gasoline(TM) and Tesoro® brands.

This release contains certain statements that are "forward-looking" statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934 concerning our expectations regarding the timing in which our Martinez, California refinery will return to normal operating levels; the timing of voting by unions at our Mandan, North Dakota and Salt Lake City, Utah refineries on their respective contracts; first quarter operating costs for our California refineries; the impact of the strike and turnarounds on our system capture rates during the first and second quarters; and the reversal during the second of the impact of increased inventory levels on working capital. For more information concerning factors that could affect these statements see our annual report on Form 10-K filed with the Securities and Exchange Commission. We undertake no obligation to publicly release the result of any revisions to any such forward-looking statements that may be made to reflect events or circumstances that occur, or which we become aware of, after the date hereof.

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Contact:

Investors:

Sam Ramraj, Vice President, Investor Relations, (210) 626-4757

Media:

Tesoro Media Relations, media@tsocorp.com, (210) 626-7702

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EX-99.2

Updated 1Q 2015 Guidance March 27, 2015 Exhibit 99.2

This Presentation includes and references “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. These statements relate to, among other things, expectations regarding refining margins, revenues, cash flows, capital expenditures, turnaround expenses and other financial items. These statements also relate to our business strategy, goals and expectations concerning our market position, future operations, margins and profitability. We have used the words “anticipate,” “believe,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “predict,” “project,” “will,” “would” and similar terms and phrases to identify forward-looking statements in this Presentation, which speak only as of the date the statements were made. Although we believe the assumptions upon which these forward-looking statements are based are reasonable, any of these assumptions could prove to be inaccurate and the forward-looking statements based on these assumptions could be incorrect. Our operations involve risks and uncertainties, many of which are outside our control, and any one of which, or a combination of which, could materially affect our results of operations and whether the forward-looking statements ultimately prove to be correct. Actual results and trends in the future may differ materially from those suggested or implied by the forward-looking statements depending on a variety of factors which are described in greater detail in our filings with the SEC. All future written and oral forward-looking statements attributable to us or persons acting on our behalf are expressly qualified in their entirety by the previous statements. We undertake no obligation to update any information contained herein or to publicly release the results of any revisions to any forward-looking statements that may be made to reflect events or circumstances that occur, or that we become aware of, after the date of this Presentation. Forward Looking Statements 2

1Q 2015 Guidance - Update 3 California Pacific Northwest Mid- Continent Consolidated Throughput (mbpd) 415 - 435 145 - 155 110 - 120 670 - 710 January1 490 – 505 165 – 170 125 – 130 February1 375 – 385 160 – 165 125 – 130 March1 375 – 385 130 - 135 110 – 115 Manufacturing Cost ($/bbl) $ 7.70 – 7.95 $ 4.15 – 4.35 $ 4.70 – 4.95 $ in millions Corporate/System Refining/ Logistics Depreciation $ 110/40 Corporate Expense Before Depreciation $ 60 Interest Expense Before Interest Income $ 63 1) Monthly throughput guidance is being provided this quarter only as a result of several unusual items which include the USW strike and idling of the Martinez refinery, along with unusually volatile margins.