IGSNs are expected to be persistent identifiers for samples and should not be deleted. For this reason no delete functionality exists within the ARDC IGSN Service.
The preferred approach is to update the IGSN's URL to point to a landing page that explains why the sample is no longer available. You may also wish to set the visibility of the IGSN to private which will prevent the IGSN from being harvested from the ARDC service by aggregators. For further information or assistance, please contact email@example.com.
The service does support updating the status of an IGSN to either Deprecated or Destroyed. This however does not delete the IGSN and simply adds a Deprecated/Destroyed event to the metadata with a timestamp.
The IGSN will continue to resolve to the URL associated with it.