Stillwater Mining Company (NYSE:SWC) Files An 8-K Entry into a Material Definitive Agreement

Item1.01

1.75% Convertible Senior Notes due 2032 (the 2032
Notes) Second Supplemental Indenture

In connection with the closing of the Merger (as defined in
Item2.01 of this Current Report on Form 8-K), Stillwater Mining
Company (the Company) and Delaware Trust
Company, as successor-in-interest to Law Debenture Trust Company
of New York (the Trustee) entered into a Second
Supplemental Indenture, dated as of May4, 2017 (the 2032
Notes Second Supplemental Indenture),
to the Indenture, dated as of November29, 2010 (the 2032
Notes Base Indenture), by and between
the Company and the Trustee, as amended and supplemented by that
certain First Supplemental Indenture, dated as of October17, 2012
(the 2032 Notes First Supplemental
Indenture and, together with the 2032 Notes Base
Indenture, as amended and supplemented by the 2032 Notes First
Supplemental Indenture and the 2032 Notes Second Supplemental
Indenture, the 2032 Notes
Indenture) relating to the 2032 Notes.

The 2032 Notes Second Supplemental Indenture provides that, at
and after the effective time of the Merger (the Effective
Time), the right to convert each $1,000 principal amount
of 2032 Notes is changed into a right to convert such principal
amount of 2032 Notes into, and the consideration due upon
conversion of each $1,000 principal amount of 2032 Notes shall be
solely, cash in an amount equal to the Applicable Conversion Rate
(as defined in the 2032 Notes Indenture), as may be increased by
Additional Shares (as defined in the 2032 Notes Indenture) to
Section10.03 of the 2032 Notes First Supplemental Indenture, in
effect on the relevant conversion date, multiplied by the Merger
Consideration (as defined in Section2.01 of this Current Report
on Form 8-K).

The foregoing description of the 2032 Notes Second Supplemental
Indenture is only a summary and is subject to, and entirely
qualified by reference to, the full text of the 2032 Notes Second
Supplemental Indenture, a copy of which is attached hereto as
Exhibit 4.1 and is incorporated by reference herein.

1.875% Convertible Senior Notes due 2028 (the 2028
Notes) First Supplemental Indenture

In connection with the closing of the Merger (as defined in
Item2.01 of this Current Report on Form 8-K), the Company and the
Trustee entered into a First Supplemental Indenture, dated as of
May4, 2017 (the 2028 Notes First Supplemental
Indenture), to the Indenture, dated as of March12, 2008
(the 2028 Notes Base Indenture and, as amended
and supplemented by the First Supplemental Indenture, the
2028 Notes Indenture), by and between the
Company and the Trustee, relating to the 2028 Notes.

The 2028 Notes First Supplemental Indenture provides that, at and
after the Effective Time, the right to convert each $1,000
principal amount of 2028 Notes is changed into a right to convert
such principal amount of 2028 Notes into, and the consideration
due upon conversion of each $1,000 principal amount of 2028 Notes
shall be solely, cash in an amount equal to the Conversion Rate
(as defined in the 2028 Notes Base Indenture) in effect on the
relevant conversion date, multiplied by the Merger Consideration
(as defined in Section2.01 of this Current Report on Form 8-K).

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The foregoing description of the 2028 Notes First Supplemental
Indenture is only a summary and is subject to, and entirely
qualified by reference to, the full text of the 2028 Notes First
Supplemental Indenture, a copy of which is attached hereto as
Exhibit 4.2 and is incorporated by reference herein).

On May4, 2017, the Company completed its previously announced
merger with Thor Mergco Inc. (Merger Sub), an
indirect wholly owned subsidiary of Sibanye Gold Limited
(Sibanye), whereby Merger Sub was merged with
and into the Company (the Merger), with the
Company remaining as the surviving corporation and as a wholly
owned subsidiary of Sibanye. At the Effective Time (as defined in
Item1.01 of this Current Report on Form 8-K), and to the terms of
the Agreement and Plan of Merger (the Merger
Agreement), dated as of December9, 2016, among the
Company, Sibanye, Thor US HoldCo Inc. (US
Holdco) and Merger Sub, each share of common stock of
the Company, par value $0.01 per share (the
Shares) outstanding immediately prior to the
Effective Time (other than Shares owned by the Company, Sibanye
or their respective subsidiaries or Shares with respect to which
appraisal rights were validly exercised and not lost in
accordance with Delaware law), was automatically canceled and
converted into the right to receive $18.00 per share in cash
without interest (the Merger Consideration).

to the Merger Agreement and in connection with the closing of the
Merger, each outstanding Company stock option and restricted
stock unit award was immediately vested and converted into the
right to receive a cash payment equal to the product of (1)the
number of Shares subject to such award and (2)the per share
Merger Consideration price (less, in the case of stock options,
the exercise price per share), less any applicable taxes.

The description of the Merger contained herein is only a summary,
is not complete and is subject to and qualified in its entirety
by reference to the full text of the Merger Agreement, a copy of
which was filed as Exhibit 2.1 to the Companys Current Report on
Form 8-K filed on December9, 2016, the terms of which are
incorporated herein by reference.

The Merger Agreement and the above description have been included
to provide investors and security holders with information
regarding the terms of the Merger Agreement. They are not
intended to provide any other factual information about the
Company, Sibanye, US Holdco and Merger Sub or their respective
subsidiaries or affiliates or equity holders. The
representations, warranties and covenants contained in the Merger
Agreement were made only for purposes of that agreement and only
as of specific dates, were solely for the benefit of the parties
to the Merger Agreement and may be subject to limitations agreed
upon by the parties, including by being qualified by confidential
disclosures made by each contracting party to the other for the
purposes of allocating contractual risk between them that differ
from those applicable to investors. Investors should be aware
that the representations, warranties and covenants or any
description thereof may not reflect the actual state of facts or
condition of the Company, Sibanye, US Holdco and Merger Sub or
any of their respective subsidiaries, affiliates or equity
holders. Moreover, information concerning the subject matter of
the representations,

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warranties and covenants may change after the date of the Merger
Agreement, which subsequent information may or may not be fully
reflected in public disclosures by the parties thereto.
Accordingly, investors should read the public disclosures of the
Company, Sibanye and their respective subsidiaries, including the
Companys filings with the U.S. Securities and Exchange Commission
(the SEC).

2032 Notes

As a result of the Merger and to the 2032 Notes Indenture,
subject to certain conditions, each holder of the 2032 Notes has
the right (the Fundamental Change Repurchase
Right), at such holders option, to require the Company
to repurchase for cash such holders 2032 Notes, or any portion of
the principal amount thereof that is equal to $1,000 or an
integral multiple of $1,000, on the Fundamental Change Repurchase
Date, as defined in the 2032 Notes Indenture (the
Fundamental Change Repurchase Date).

In addition, to the terms and conditions of the 2032 Notes
Indenture, the 2032 Notes are currently convertible at the option
of the holders thereof. Holders of 2032 Notes have the right,
subject to certain conditions, at such holders option, to
surrender the 2032 Notes for conversion to Continental Stock
Transfer Trust Company, as conversion agent (the
Conversion Agent) at any time from and including
April27, 2017, the business day after the Company gave holders
notice of the Merger (as defined in Item2.01 of this Current
Report on Form 8-K), until the Fundamental Change Repurchase Date
(the Conversion Period). If a holder surrenders
2032 Notes for conversion to the Conversion Agent at any time
from and including May4, 2017, the date on which the Make-Whole
Fundamental Change occurred, the Business Day immediately prior
to the Fundamental Change Purchase Date (such period, the
Make-Whole Conversion Period), the Companys
conversion obligation with respect to each $1,000 principal
amount of 2032 Notes that are converted during the Make-Whole
Conversion Period is fixed at an amount in cash equal to the
Applicable Conversion Rate of 75.2905 (such Applicable Conversion
Rate including additional shares of Company Common Stock as
provided in the Indenture) for each $1,000 principal amount of
the Notes, multiplied by $18.00 (i.e., the Merger Consideration).
If a holder surrenders 2032 Notes for conversion before or after
the Make-Whole Conversion Period, but during the Conversion
Period, a holder would receive an amount in cash equal to the
Applicable Conversion Rate of 62.9664 for each $1,000 principal
amount of the 2032 Notes, multiplied by $18.00 (i.e., the Merger
Consideration). The Company intends to provide notice to holders
regarding the procedures and terms for the repurchase and
conversion of the 2032 Notes within 10 business days following
the Merger, in accordance with the terms of the 2032 Notes
Indenture.

Assuming that each holder exercised the Fundamental Change
Repurchase Right, the Company would be obligated to make
aggregate payments of approximately $336million.

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Assuming that each holder exercised the conversion right in
connection with the Merger during the Make-Whole Conversion
Period, the Company would be obligated to make aggregate payments
of approximately $454.2 million.

Assuming that each holder exercised the conversion right in
connection with the Merger during the Conversion Period but not
during the Make-Whole Conversion Period, the Company would be
obligated to make aggregate payments of approximately $379.9
million.

The right of holders to convert their 2032 Notes is separate from
the Fundamental Change Repurchase Right. Holders may only
exercise one of either the Fundamental Change Repurchase Right or
the conversion right.

On April28, 2017, the Company filed with the SEC an application
on Form 25 in order to delist and to deregister the Shares under
Section12(b) of the Securities Exchange Act of 1934, as amended
(the Exchange Act).

On or about May8, 2017, the Company intends to file with the SEC
a Form 15 that requests that the reporting obligations of the
Company under Sections 13 and 15(d) of the Exchange Act be
suspended.

The information contained in Items 2.01, 3.01, 5.01 and 5.03 of
this Current Report on Form 8-K is incorporated by reference into
this Item 3.03.

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A change of control of the Company occurred on May4, 2017 upon
the filing of the certificate of merger with the Secretary of
State of the State of Delaware, at which time Merger Sub merged
with and into the Company. As a result of the Merger, the Company
became an indirect, wholly owned subsidiary of Sibanye.

The disclosures under Item 2.01 and Item 3.01 above are
incorporated herein by reference.

In accordance with the terms of the Merger Agreement, at the
Effective Time, Richard Stewart and Charl Keyter, the directors
of Merger Sub immediately prior to the Effective Time, became the
directors of the Company. Accordingly, each of George M. Bee,
Michael J. McMullen, Patrice E. Merrin, Lawrence Peter OHagan,
Michael S. Parrett, Brian D. Schweitzer and Gary A. Sugar ceased
serving as members of the Companys board of directors as of the
Effective Time. In accordance with the terms of the Merger
Agreement, at the Effective Time, the officers of the Company
immediately prior to the Effective Time continued to serve as
officers of the Company.

At the Effective Time on May4, 2017 and to the Merger Agreement,
(i)the certificate of incorporation of Merger Sub, as in effect
immediately prior to the Effective Time, became the Amended and
Restated Certificate of Incorporation of the Company (the
Amended and Restated Certificate of
Incorporation), as the surviving corporation in the
Merger; and (ii)the bylaws of Merger Sub, as in effect
immediately prior to the Effective Time, became the Amended and
Restated Bylaws of the Company (the Amended and Restated
Bylaws), as the surviving corporation in the Merger,
except that, in each case, references to the name of Merger Sub
have been replaced with references to the name of the Company.

The foregoing descriptions of the Amended and Restated
Certificate of Incorporation and the Amended and Restated Bylaws
are not complete and are subject to and qualified in their
entirety by reference to the Amended and Restated Certificate of
Incorporation and the Amended and Restated Bylaws, copies of
which are attached hereto as Exhibit 3.1 and Exhibit 3.2,
respectively, and are incorporated herein by reference.

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About Stillwater Mining Company (NYSE:SWC)

Stillwater Mining Company is engaged in the development, extraction, processing, smelting and refining of palladium, platinum and associated metals, such as platinum group metals (PGM) produced by mining a geological formation in south-central Montana, the J-M Reef and recycling spent catalytic converters and other industrial sources. The Company operates through five segments: Mine Production, PGM Recycling, Canadian Properties, South American Properties and All Other. The Mine Production segment consists of two business components: the Stillwater Mine and the East Boulder Mine. The PGM Recycling segment recycles spent catalyst material to recover the PGMs contained in the material. The Canadian Properties segment consists mainly of the Marathon mineral property assets. The South American Properties segment consists of the Peregrine Metals Ltd. assets. The All Other segment consists of assets, including investments, revenues, and expenses of various corporate and support functions.

Stillwater Mining Company (NYSE:SWC) Recent Trading Information

Stillwater Mining Company (NYSE:SWC) closed its last trading session at 0.0000 with 3,015,042 shares trading hands.