No. The properties are in a separate, likely US company. But this company is wholly owned by the current CUU. If the buyout is in the form of share purchase, then Teck (assuming it's Teck who buys us out), by virtue of owning all the OS shares of CUU, would also own the US subsidiary.

To spin that off, CUU has to first set up a CUU2, have CUU2 acquire the US sub; then when Teck buys out all the CUU shares, it would not also own the sub with the AZ properties. A minor legal inconvenience but must be taken care of.