An orphan dataset is one where GBIF has been unable to access it from the original publisher's system for a long time, typically at least six months.
A rescued dataset has the last available data exported by GBIF and made available here. This makes it easier for publishers and/or GBIF Nodes and Participants to restore datasets in cases where they have been lost.
It is generally not GBIF's goal to be the primary source for a dataset.
This server holds rescued datasets; that is, those that were not available from the original data provider and have been exported. See the project documentation for more information, and What is an orphan dataset? in the GBIF.org FAQ.