Armory was a poor chimneysweep who found a jeweled ring.
He took it to a jeweler who removed the jewel and told him that the empty
ring was only worth 3 halfpence. Armory sued in trover.
Trover is an old common law action for money
damages resulting from the defendant taking or using something rightfully
belonging to the plaintiff.
In most US courts, this is now referred to as conversion.
This is different from replevin, where you are
suing to get your stuff back, as opposed to just getting money.
The English Court found for Armory.
The English Court found that the finder of an object
might not have absolute ownership of it, but he has the right to keep it
against all by the rightful owner.
If the jeweler didn't produce the jewel, the English Court ordered him to pay an amount equal to the finest jewel that could fit
into the empty socket.
The basic rule is that if you find an object, it is yours
unless the original owner demands its return.
What would have happened if Delamirie paid Armory for the
jewel, then the true owner of the jewel shows up and sues Delamirie for replevin?
Doesn't Delamirie get kinda screwed?
This is one reason why courts prefer you to sue for replevin
than for trover. That causes fewer problems, since if Delamirie
just gave the jewel back to Armory, then the true owner could sue Armory
and things would be simpler.
If Delamirie can never own 100% of the jewel (since he'll
have to give it back to the new owner), why should he have to pay Armory
for 100% of the value?