The Ring of the Darkhidden is found in the Magic Item Compendium page 122 and says:
You are invisible to darkvision, although you are fully visible in normal light.
How do spells such as See Invisibility, Invisibility Purge, True Seeing, or other such spells/abilities interact with the ring's effect? I'm assuming True Seeing works since it trumps everything illusion, but what about the others? Invisibility works on both vision and darkvision, so is the ring's effect simply discount invisibility or would it count as a different enough effect to bypass spells that only trip on "invisibility"?