I always assumed that this could not make its way into the ledger, but while testing with (seemingly) invalid transactions, I created the following:
A custom asset
I created a custom asset. As you can see in the lab explorer, I issued an amount of 4000 units.
I funded a new account
I created a transaction for the account to send itself much more of the asset that it owns
Actually, way more of the asset than actually exists. There were 4000 issued, but I sent a payment over 12312312313.0000000.
Good thing: It did not actually get applied
When we look at the account we see that I was not able to overspend.
Confusing: Why was this transaction successful and made it into the ledger?
This is confusing to me. I would have assumed that this would not be accepted into the ledger. I would be very grateful for some hints, why this happened :)