Thought some might find this interesting

Excerpts from the NM Commentary (5Dec11):

The effect of an NPI royalty is to make the holder a partner in the enterprise by withholding payments to them until the operator has been reimbursed for their expenses, and then sharing the profits. The NPI royalty sturcture is prone to manipluation and has acquired the reputation as the "no payment intended" royalty. IE: pay CUU/TECK first, then NPI holder

The effect of an NPI is to delay the payment of royalty payments for an extended period of time after production begins.

The most widely used royalty structure is the NSR royalty, which is a % of the gross revenues from the sale of mineral product from a property by the mine operator to a treatment plant, with minimal deductions for transportation costs..