MATR MATTR Corporation

Shawcor Ltd., dba Mattr Infratech (“Mattr” or the “Company”) (TSX: MATR) announced today that its common shares will be added to the S&P/TSX Composite Index, effective prior to market open on Monday, September 18, 2023. The S&P/TSX Composite Index is the headline index and principal benchmark for Canadian equity markets.

“Inclusion in the S&P/TSX Composite Index is an important milestone that would not have been possible without the hard work and dedication of our employees around the world. Over the past three years, Mattr’s global team has demonstrated extraordinary creativity, invention and commitment - substantially expanding the delivery of high-value products to critical infrastructure markets and accelerating the development of new technologies,” said Mike Reeves, President and CEO of Mattr. “I would like to thank our investors for their continued support of our strategy. This inclusion will serve to enhance the visibility of our Company and increase our reach across a broader investor base.”

About MattrMattr is a growth-oriented, global materials technology company broadly serving critical infrastructure markets, including electrification, transportation, communication, water management and energy. Its two business segments, Composite Technologies and Connection Technologies, operate a global network of manufacturing and technology centers, delivering differentiated, high-value products which enable responsible renewal and enhancement of critical infrastructure while lowering risk and environmental impact.

For further information, please contact:

Meghan MacEachernDirector, External Communications & ESG Telephone: 437.341.1848Email: meghan.maceachern@mattr.comWebsite: www.mattr.com

Forward Looking Information

This news release contains forward-looking information within the meaning of applicable securities laws. Words such as "may", "will", "should", "anticipate", "plan", "expect", "believe", "predict", "estimate" or similar terminology are used to identify forward-looking information. This forward-looking information is based on assumptions, estimates and analysis made in the light of the Company's experience and its perception of trends, current conditions and expected developments, as well as other factors that are believed by the Company to be reasonable and relevant in the circumstances. Forward-looking information involves known and unknown risks, uncertainties and other factors which may cause actual results, performance or achievements to be materially different from those predicted, expressed or implied by the forward-looking information. The forward-looking information is provided as of the date of this news release and the Company does not assume any obligation to update or revise the forward-looking information to reflect new events or circumstances, except as required by law.

Source: Shawcor Ltd., dba Mattr Infratech