04:34 PM EDT, 03/31/2025 (MT Newswires) -- Birchtech ( BCHT ) after trade Monday said it swung to a fourth-quarter loss while its revenue rose year-over-year.

The company lost US$1.3 million, or US$0.01 per share, in the period, compared with earnings of US$9 million, or US$ 0.09, in the year-ago quarter.

Revenue for the quarter ended Dec. 31 rose 37% to US$5.6 million from US$4.1 million a year ago. The company said the increase was mainly due to higher licensing revenues in the quarter, offset by reduced product sales.

"Financially, we believe our air business will generate at least $23 million in revenue in 2025, excluding any cash received from legal claims, and excluding water treatment revenue as well. In 2026, we believe our air business annual revenue run-rate has the potential to further scale to $40 million," Chief Executive Richard MacPherson said.

Birchtech ( BCHT ) shares last traded Friday, closing at $0.72 on the Toronto Stock Exchange.