Which one of the following is not a legal incident of 'Waqf'?

Irrevocability, perpetuity and inalienability are the recognised legal incidents of a valid waqf, which is a permanent dedication of property for purposes recognised by Muslim law as pious, religious or charitable (section 3(r) of the Waqf Act, 1995). "Universal" is not one of those incidents, so it is the answer.