Teck can acquire 10% (~40M shares) without any disclosure. Once over 10% they have 10 days to file their position on sedi. If they go over 20% they become a control block. Not sure if CUU has a shareholder rights plan but if they do then acquiring any shares over 20% would require an offer to all shareholders otherwise they can only buy 2% at a time and need to disclose each time they cross that 2% threshold.