Lundin Mining Corporation, et al. v. Dov Markowich

What constitutes a “material change” for the purpose of Canadian securities law under the Securities Act, R.S.O. 1990, c. S.5, ss. 138.3(4) and 138.8?

Should the requirement for leave to proceed in securities-related actions modify or lessen the burden to show a “material change”?

What are the legal implications of a mining company disclosing pit wall instability and a subsequent rockslide in periodic disclosures rather than at the time of occurrence?