PolyMet Events and News

June 27, 2013

PolyMet Reminder to Shareholders Rights Offering Closes at 5:00 pm Eastern Time on July 3, 2013

St. Paul, Minnesota, June 27, 2013 – PolyMet Mining Corp. (TSX: POM and POM:RT; NYSE MKT: PLM and PLM.RT) (PolyMet or the Company) would like to provide a friendly reminder to its shareholders that its previously announced Rights Offering will remain open until 5:00 p.m. (Eastern time) on Wednesday July 3, 2013. Rights holders will need to exercise their subscription rights prior to that time and date.

Rights holders can subscribe for one new common share of PolyMet for US$0.66 per share for every two Rights held.

Rights will cease trading on the NYSE MKT: PLM.RT at the close of trading on Tuesday, July 2, 2013 and on the TSX: POM.RT at 12:00 noon (Eastern time) on Wednesday July 3, 2013. Please note that Canadian banks and markets will be closed on Monday July 1, 2013 for Canada Day.

All questions should be directed to Stephanie Hunter, PolyMet’s Corporate Secretary, at:
Tel: +1 (416) 915-4149
Fax: +1 (416) 915-4189
Email: shunter@polymetmining.com

Copies of the Rights Offering materials may be obtained from the Company by calling +1 (651) 389-4100 or Computershare Investor Services Inc., the subscription agent for the Company, at +1 (800) 564-6253.

Rights have been offered to shareholders under a prospectus filed with the applicable securities regulators of Ontario, British Columbia, Alberta, and in the United States. Please contact PolyMet or the subscription agent if you have any questions regarding the Rights Offering or require assistance in exercising your Rights. For further information on the Rights Offering, please refer to: http://polymetmining.com/investors/investor-faq/

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About PolyMet
PolyMet Mining Corp. (www.polymetmining.com) is a publicly-traded mine development company that owns 100% of Poly Met Mining, Inc., a Minnesota corporation that controls 100% of the NorthMet copper-nickel-precious metals ore body through a long-term lease and owns 100% of the Erie Plant, a large processing facility located approximately six miles from the ore body in the established mining district of the Mesabi Range in northeastern Minnesota. Poly Met Mining, Inc. has completed its Definitive Feasibility Study and is seeking environmental and operating permits to enable it to commence production. The NorthMet Project is expected to require approximately two million hours of construction labor, creating approximately 360 long-term jobs, a level of activity that will have a significant multiplier effect in the local economy.

PolyMet Mining Corp

Per:Jon Cherry
Jon Cherry, CEO

For further information, please contact:

Douglas Newby
Chief Financial Officer
Tel: +1 (651) 389-4105

LaTisha Gietzen
VP Public, Govt & Environmental Affairs
Tel: +1 (218) 471-2150

Jenny Knudson
VP Investor Relations
Tel: +1 (651) 389-4110

MZ North America
Pascal Nigen
Senior Vice-President
Tel: +1 (212) 301-7149


This news release contains certain forward-looking statements concerning anticipated developments in PolyMet’s operations in the future. Forward-looking statements are frequently, but not always, identified by words such asexpects, anticipates, believes, intends, estimates, potential, possible, projects, plans, and similar expressions, or statements that events, conditions or results will, may, could, or should occur or be achieved or their negatives or other comparable words. These forward-looking statements may include statements regarding our beliefs related to the closing of the Rights Offering, the ability to receive environmental and operating permits, job creation, or other statements that are not a statement of fact. Forward-looking statements address future events and conditions and therefore involve inherent known and unknown risks and uncertainties. Actual results may differ materially from those in the forward-looking statements due to risks facing PolyMet or due to actual facts differing from the assumptions underlying its predictions.

PolyMet’s forward-looking statements are based on the beliefs, expectations and opinions of management on the date the statements are made, and PolyMet does not assume any obligation to update forward-looking statements if circumstances or managements beliefs, expectations and opinions should change.

Specific reference is made to PolyMet’s most recentAnnual Report on Form 20-F for the fiscal year ended January 31, 2013 and in our other filings with Canadian securities authorities and the U.S. Securities and Exchange Commission, including our Report on Form 6-K providing information with respect to our operations for the three months ended April 30, 2013for a discussion of some of the risk factors and other considerations underlying forward-looking statements.

The TSX has not reviewed and does not accept responsibility for the adequacy or accuracy of this release.

PolyMet has filed a registration statement (including a prospectus) with the U.S. Securities and Exchange Commission, for the offering to which this communication relates. Before investing, prospective investors should read the prospectus in that registration statement and other documents the issuer has filed with the U.S. Securities and Exchange Commission, for more complete information about PolyMet and this offering. The documents are available free of charge by visiting EDGAR on the U.S. Securities and Exchange Commission website at www.sec.gov. Alternatively, PolyMet will arrange to send you the prospectus if you request it by calling1-416 915-4149.