Exercise of options

1 September 2016

Sirius Minerals Plc

Exercise of options

Sirius Minerals Plc (AIM: SXX, OTCQX: SRUXY) ("Sirius" or the "Company") announces the receipt of an exercise notice in relation to 250,000 share options granted to a former employee in August 2011.

The Company has issued and alloted 250,000 new ordinary shares of 0.25p per share at an exercise price of 16.3p per share ("Ordinary Shares"). An application has been made for the Ordinary Shares, which will rank pari passu with the Company's existing ordinary shares, to be admitted to trading on AIM with admission expected to take place at 8.00 am on 5 September 2016.

Following admission of the Ordinary Shares, the Company's enlarged issued share capital will comprise 2,313,619,115 ordinary shares with voting rights. This figure may be used by shareholders in the Company as the denominator for the calculations by which they will determine if they are required to notify their interest in, or a change in their interest in, the share capital of the Company under the FCA's Disclosure and Transparency Rules.

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About Sirius Minerals Plc

Sirius Minerals is the fertilizer development company focused on the development of its North Yorkshire polyhalite project, the United Kingdom. It has the world's largest and highest grade deposit of polyhalite, a multi-nutrient form of potash containing potassium, sulphur, magnesium and calcium. Incorporated in 2003, Sirius Minerals' shares are traded on the London Stock Exchange's AIM market. Its shares are also traded in the United States on the OTCQX through a sponsored ADR facility. Further information on the Company can be found at: www.siriusminerals.com.