9 September 2019

Mosman Oil and Gas Limited

 ("Mosman" or the "Company")

Stanley-3 Initial Production Flow Rates

Mosman Oil and Gas Limited (AIM: MSMN) the oil exploration, development and production company, advises that the Stanley-3 well in Texas has been completed.

Mosman has been advised that a six foot interval within the 4,800 Sand was perforated during well completion operations. During flow testing, the stabilised rate from this interval was 192 BOPD on an 8/64" choke. The recovered fluid is 100% oil.

The optimal production rate for this reservoir will be determined by the Operator in due course.

Mosman has a 14.85% working interest in this well.

John W Barr, Chairman, said: "We are delighted with the progress at Stanley, with Stanley-3 delivering significant commercial success, as we build on our production growth. This further reinforces the whole investment strategy pursued by Mosman, and we look forward to continued success with Stanley-4 being the next well to be evaluated."

Competent Person's Statement

The information contained in this announcement has been reviewed and approved by Andy Carroll, Technical Director for Mosman, who has over 35 years of relevant experience in the oil industry. Mr. Carroll is a member of the Society of Petroleum Engineers.

Market Abuse Regulation (MAR) Disclosure

Certain information contained in this announcement would have been deemed inside

information for the purposes of Article 7 of Regulation (EU) No 596/2014 until the release of this announcement.

 Enquiries:

Updates on the Company's activities are regularly posted on its website www.mosmanoilandgas.com

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