The difference lies in the minimum amount invested. With the new agreement, Teck only had to pay $24M to earn 75%. With the old agreement, Teck had to pay $350M before they earned their 75%.

Teck has no obligation to spend $60M on exploration and no obligation to payout the other $40M to CUU. If they don't like what they see, they can stop spending money on it and still have their 75%. I like the new agreement because it limits dilution but I hate how there is no obligation for Teck to spend money exploring.