UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K/A

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): October 13, 2015

Fortress Investment Group LLC

(Exact name of registrant as specified in its charter)

Delaware

(State or other jurisdiction

of incorporation)

Registrant’s telephone number, including area code (212) 798-6100

N/A

(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. below):

The information set forth in Item 8.01 is incorporated herein by reference in its entirety.

On October 13, 2015, the Company issued a press release announcing the closing of the Fortress Macro Fund, retirement of Principal, director and Fund CIO Michael Novogratz and expected repurchase of Mr. Novogratz’s ownership interests.

The full text of the press release is included in Exhibit 99.1 hereto and is incorporated by reference herein in its entirety.

Cautionary Note Regarding Forward-Looking Statements

Certain statements in this Current Report may constitute “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. These statements are generally identified by the use of words such as “outlook,” “believe,” “expect,” “potential,” “continue,” “may,” “will,” “should,” “could,” “would,” “seek,” “approximately,” “predict,” “intend,” “plan,” “estimate,” “anticipate,” “opportunity,” “pipeline,” “comfortable,” “assume,” “remain,” “maintain,” “sustain,” “achieve” or the negative version of those words or other comparable words. Forward-looking statements are not historical facts, but instead represent only the Company’s beliefs as of the date of this report regarding future events, many of which, by their nature, are inherently uncertain and outside of the Company’s control. Numerous factors could cause actual events to differ from these forward-looking statements. Accordingly, you should not place undue reliance on any forward-looking statements contained in this Current Report, and you should not regard any forward-looking statement as a representation by the Company or any other person that the future plans, estimates or expectations currently contemplated by the Company will be achieved. The Company can give no assurance that the expectations of any forward-looking statement will be obtained. Such forward-looking statements speak only as of the date of this Current Report. The Company expressly disclaims any obligation to release publicly any updates or revisions to any forward-looking statements contained herein to reflect any change in the Company’s expectations with regard thereto or any change in events, conditions or circumstances on which any statement is based.

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SIGNATURE

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: October 14, 2015

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EXHIBIT INDEX

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