Nevertheless, the contract states that if Teck elects to proceed to earn-back 75% they may, if in their sole opinion they deem warranted, make a decision to place the property into commercial production by constructing a mine and related infrastructure. It's all there in the Agreement.

They have to spend the money to earn back their share, but they do not have to make the decision to go ahead and put the mine into production. They could spend the money doing more exploration work or whatever, but they cannot be forced by that clause into production.

What we don't know, is how the 4-year back-in clause is written that presumably would force their hand somewhat, or at what point that clause is triggered.

The 75% does become effective after they've earned it by spending the money somehow.