Marking a ball on the green Rule 15.3

[salfordlad]

I did not cut and paste the whole rule because it was not relevant to my question

15.3 Ball or Ball-Marker Helping or Interfering with Play
a. Ball on Putting Green Helping Play
Rule 15.3a applies only to a ball at rest on the putting green, not anywhere else on the course.

Another distinction is 15.3a relates only to a helping ball on the putting green, an interfering ball anywhere on the course is dealt with in 15.3b.