Virtual IBAN
A perfectly valid IBAN with no account of its own behind it, used to route incoming payments into an underlying master account.
To the payer it looks like any other IBAN, and the check digits add up. The bank, however, books the money to a master account and uses the number itself to tell who sent it. A company can hand every customer or every invoice its own number and stop guessing which payment belongs to what, a problem otherwise left to references that payers forget or mistype.
The other use is geographic. Fintechs give customers all over Europe IBANs with, say, a Lithuanian or Belgian country code, issued through a partner bank. The SEPA Regulation bans refusing an IBAN from another SEPA country, yet employers and public agencies do it anyway, and the practice has earned the name IBAN discrimination. Regulators, meanwhile, have flagged virtual IBANs as a money-laundering risk, since the number says nothing about who actually holds the account.