Some communities want lipids in pathways only annotated LIPID MAPS identifiers. This test checks if only those are used.
The pathway is using identifiers for molecules from other databases than LIPID MAPS.
If the test fails, you can look up the LIPID MAPS identifier for the compound in the pathways that was not using a LIPID MAPS identifier. The GPML source of the pathway can then be updated to list the new identifier.