Abstract
Patents are playing an increasingly important role in today’s business world. A patent portfolio can enable a company to secure a monopoly within the market, which can provide a commercial advantage over competitors. At the same time, possessing a patent portfolio increases the value of a company’s intangible assets.
The importance of critical minerals is being rapidly recognized by governments worldwide. One recently identified route to recovering critical minerals is through the hydrometallurgical processing of mining waste, such as tailings and waste rock. The Government of Ontario has established Ontario’s Critical Minerals Strategy 2022–2027, which includes an amendment to the Mining Act in 2021 to allow for the reprocessing of mining waste, without the requirement to file a mine production closure plan or obtain a mining lease. At the same time, Ontario’s Critical Minerals Innovation Fund identifies extraction of additional value from mining waste as a key innovation area in need of further development, and is providing up to $0.5 million in funding for development of such projects.
Companies and research institutions worldwide are racing to develop, and ultimately commercialize, processes and technologies for processing of mining waste to recover critical minerals. These new processes and technologies are routinely patented soon after they are developed, as a step toward monetization. Analysis of this patent filing data can provide a unique, combinatorial picture of both research and commercial activities within the field.
The present study looks at patent filing trends in the field of hydrometallurgical processing of mining waste for recovery of critical minerals over the decade spanning 2015 to 2025. The data shows a generally constant rate of annual patent filings from 2015 to 2023, followed by a sharp increase in the number of filings in 2024 and 2025, presumably reflecting recent international recognition of this new approach as a commercially viable route to recovering critical minerals. Patent filings in China, Australia, the U.S. and Canada accounted for over 95% of all filings. Interestingly, the bulk of patent filings by Chinese entities were in China only, while patents filed by entities outside China were filed more internationally and in multiple jurisdictions, providing an interesting indicator as to anticipated commercial activity by those entities in those different global markets.
On a technological level, the patent filing data shows a sharp increase in 2024 and 2025 in the number of patents filed for processes for lithium recovery, while filings for processes for recovery of copper, nickel, cobalt and rare earth metals exhibited individual maxima prior to 2024 and 2025.
A more granular analysis of the above data and findings, as well as recommended patent filing strategies for researchers in view of the current patent landscape portrayed by the data, will be provided.