Sentence:  A 5 - percent royalty is paid on any production during the period the contract is in effect ; if the Government certifies that production may be possible from the property , the royalty <WSD>obligation</WSD> continues for the 10 - year period usually specified in the contract or until the Government 's contribution is repaid with interest . 
Meaning of the word marked with <WSD> tags:  the social force that binds you to the courses of action demanded by that force; every opportunity, an obligation; every possession, a duty"- John D.Rockefeller Jr