What is meant by “provenance is likely required”? What rationale is acceptable to ESCRO for requesting to waive provenance?

In general, provenance documentation is required for any non-federally approved hESC-line(s). An exception to this requirement may include when induced pluripotent stem cell lines are created from anonymized somatic cell sources where the PI cannot ascertain the identity of the individual who donated the somatic cell. In such cases, the PI should briefly explain the history of the cell line and cite relevant literature supporting the origin of the cell line.