The Supreme Court of Canada Speaks to What Constitutes a Material Change
The Supreme Court of Canada has affirmed a broad interpretation of what constitutes a “material change”. Here’s what issuers need to know.

In 2017, a rockslide occurred at a Chilean copper mine. No one was hurt and no equipment was damaged, but the debris restricted access to the mine. As a result, the mine’s owner, TSX-listed Lundin Mining Corp., shut down parts of the mine, revised its production schedule downward by 20%for the following year, and decided to rely to some extent on lower-grade stockpiles of ore instead.
Lundin did not immediately disclose the rockslide and consequential operational changes. Instead, investors were informed in a periodic update roughly a month later. The following trading day, Lundin’s share price dropped by about 16%, erasing over $1 billion in value. Lundin’s then-CEO called it a “black eye” for the company, and apologized to investors for not communicating well enough about the event.
Those developments formed the backdrop for a legal battle that worked its way up to the Supreme Court of Canada, focused on “perhaps the most difficult area of securities law”: the distinction between a material fact and a material change.
Whether the rockslide and its consequences represented a material fact or a material change would dictate whether Lundin was offside its timely disclosure obligations by not disclosing these developments immediately. Where an issuer has not complied with its timely disclosure requirements, investors have a right of action for damages against the issuer together with each of its directors, officers, and certain others pursuant to the Securities Act (Ontario). This right of action can be powerful, because unlike other remedial options, investors do not need to prove that they relied upon the issuer’s omission or misrepresentation. To guard against frivolous litigation, the Act requires that a party obtain leave of the court before proceeding with a claim.
In its 2007 decision in Kerr v. Danier Leather Inc., the Supreme Court considered whether a change in a company’s operating results amounted to a material change requiring immediate disclosure. Lunding Mining Corp. v. Markowich builds on the principles set out in Kerrby refusing to reduce the elements of the term “material change” to restrictive definitions, and confirming the legal test an investor must meet in order to be granted leave to sue a company for failure to make timely disclosure.
Here are the key highlights of the Supreme Court’s decision, and what it means for the disclosure obligations of publicly listed issuers in Canada.
Distinguishing between a material fact and a material change is a contextual exercise that can give rise to considerable uncertainty, as the Court acknowledged.
Over time, case law and commentary have yielded certain guiding principles:
As the Supreme Court has previously confirmed, such as in Kerr, the distinction between a “material fact” and a “material change” is deliberate and policy-based: it is meant to relieve reporting issuers of the obligation to continually interpret external developments as they affect the affairs of the issuer, unless the external change would result in a change in the business, operations or capital of the issuer.
In Lundin, the Court observed that the distinction between a material fact and a material change helps to remedy informational asymmetry between issuers and investors: while information about external events is often in the public domain, the impact of those external developments on an issuer, together with internal changes in the issuer’s business, operations, or capital may be much less available to investors. Requiring immediate disclosure of such changes, where they are material, helps to “level the informational playing field.”
Case law and regulatory guidance can be illustrative of what does, and does not, constitute a material change:
In their policies, some stock exchanges give examples of developments that might qualify as a change in an issuer’s business, operations, or capital. For example, the TSX in its guide to timely disclosure requirements states that updates which are likely to require disclosure include:
A court will apply the following two-part analysis in considering whether a “material change” has occurred:
Whether a material change has occurred will depend on the issuer and its business context; there is no bright-line test for making this determination. Issuers must apply their industry knowledge, their familiarity with their own business, operations, and capital, and simple common sense in order to assess whether a change has occurred and whether it is material.
As noted in Peters v. SNC-Lavalin Group Inc., a material change can also include the risk of a change in the business, operations or capital of an issuer.
The Act relies on the ordinary commercial meaning of “business”, “operations”, and “capital” and does not provide definitions of these terms. Issuers should apply a holistic standard for assessing corporate developments that could amount to a change.
Changes in a company’s business, operations, or capital do not include external events or performance results on their own, even if they are likely to significantly affect the company’s stock price or might otherwise qualify as a material fact. The material change reporting obligation is not an obligation to provide a running commentary on internal or external events that may impact a company’s performance.
While external events could prompt changes to an issuer’s operations, and financial results can be a reflection of changes that have been made, the disclosure requirement is triggered by the change in the issuer’s business, operations, or capital itself.
Negotiations and internal deliberations, without more, typically would not amount to a change in the business, operations, or capital of the issuer, even if they are material.
A development need not be important or substantial in order to constitute a “change”. The magnitude of the change is only considered in the second step of the test.
Having found a change to have occurred, the next step is to determine if it is material, which means that it would reasonably be expected to have a significant effect on the market price or value of the issuer’s securities.
Materiality is determined from the perspective of the reasonable investor, and is a strictly economic analysis. The impact on price or value must reasonably be expected to be significant in order to meet the threshold.
The Ontario Securities Commission has advised that in borderline cases, issuers should err on the side of disclosure, and resist getting caught up in technical interpretations of securities laws.
If a material change has occurred, a reporting issuer must immediately issue a press release and file it on SEDAR+. It must also produce a material change report, including information such as a more fulsome description of the material change together with the identity and contact information of an executive officer who is knowledgeable about the change. Issuers with mineral projects or oil and gas activities must comply with certain additional disclosure requirements.
A material change report must be filed on SEDAR+ within 10 days of the change.
Securities laws prohibit trading by a person in a “special relationship with an issuer” where that person has knowledge of a material fact or material change that has not been generally disclosed. Issuers may also have blackout policies governing when insiders may not buy or sell securities.
In assessing whether the threshold for leave has been met, courts must “undertake a reasoned consideration of the evidence to ensure that the action has some merit”. The Supreme Court affirmed the following principles:
Initially, the motion judge dismissed Mr. Markowich’s motion for leave, on the basis that there was no reasonable possibility that the rockslide constituted a material change in Lundin’s operations, since pit wall failure was a known risk of open pit mining, and the events did not affect Lundin’s commercial viability. Importantly, the motion judge relied on a dictionary definition of “change”, and on case law interpretations of“business,” “operations” and “capital”, rather than interpreting these words in context and with recognition that the legislature intentionally left the words undefined in the Act in order for them to acquire meaning by being applied in specific factual circumstances.
However, the motion judge also stated that if he had found a change in Lundin’s business, operations or capital, there was a reasonable possibility that any such change was material, based on expert evidence Mr. Markowich had presented and on the concern exhibited by investors on the conference call after Lundin’s disclosure was ultimately made.
The Court of Appeal overturned the motion judge’s ruling and granted Mr. Markowich leave to proceed with his statutory cause of action. That court found that the motions judge had interpreted the definition of “material change” too narrowly, especially at the early stage of a motion for leave of the court.
The Supreme Court dismissed Lundin’s appeal and took the opportunity to expressly reject the motion judge’s interpretation of the words “change”, “business”, “operations”, and “capital”. The Court emphasized that the legislature had intentionally declined to define these key terms in the Act, and that allowing them to retain their ordinary meaning allows for their application in a wide variety of factual scenarios, maximizing the extent to which the “informational playing field” between companies and investors is levelled.
As to the test for leave of the court, there was no dispute that Mr. Markowich’s action against Lundin was brought in good faith. As to the second step of the test, the Court noted that the motions judge had accepted that the rockslide resulted in a change in Lundin’s operations which could possibly be shown to be material at trial.
The Court concluded that based on a plausible statutory analysis, there was a reasonable possibility that Mr. Markowich could succeed at trial in showing that material changes had developed which Lundin should have disclosed forthwith. Therefore, Mr. Markowich should have been granted leave to bring an action for the alleged breach of Lundin’s timely disclosure obligations.
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