SCC's Lundin Decision Signals Broad, Contextual Approach To "Material Change"

On November 28, 2025, the Supreme Court of Canada (SCC) released its long-anticipated decision in Lundin Mining Corp v Markowich (Lundin), offering significant guidance on the interpretation of "material change" under Canadian securities law.

Background

As discussed in our earlier article, securities law distinguishes between material facts and material changes. A material change occurs when there is a change in the issuer's business, operations, or capital that would reasonably be expected to have a significant effect on the market price or value of its securities.¹ A material fact, on the other hand, is any fact that that would reasonably be expected to have a significant effect on the market price or value of its securities.² While material facts may be disclosed through periodic reporting, material changes trigger an obligation of immediate public disclosure.