Issuer powers and why they exist

XRP has no issuer. No one can freeze it or take it back on the ledger. An exchange can still freeze XRP it holds for you, because the exchange controls that account, not you.

Tokens are different. A token is a balance that an issuer created, and the issuer can keep extra powers over it:

• Freeze stops one holder from sending the token, except back to the issuer.
• Deep Freeze also stops that holder from receiving it.
• Global Freeze stops every holder at once.
• Clawback takes tokens back from a holder.

Why would anyone want this? Some issuers must follow financial rules. A stablecoin issuer may have to recover tokens sent to an account sanctioned for illegal activity. Other reasons in the docs include a stolen issuing key, a move to a new issuing account, and closing down.

Issuers can also give a power up. No Freeze is a permanent promise not to freeze single holders. An issuer uses it to make a token behave more like cash between holders.

These powers cut both ways. They help an issuer meet the law and respond to theft. They also mean the issuer can stop your tokens. And the ledger cannot force any issuer to honor what its tokens stand for. That is why the issuer matters as much as the token.

Holders can freeze too. Freezing your own line to an issuer stops others sending you that token. It does little else.

Freeze settings live in two places:

• Individual and deep freezes are flags on one RippleState entry, which is one trust line.
• Global Freeze, No Freeze and Allow Trust Line Clawback are flags on the issuer's AccountRoot.

Account-level settings apply to every trust line token that account issues. You cannot globally freeze one currency code and not another. xrpl.org recommends a separate issuing account for each token for this reason.

Three amendments added the newer powers:

Dates come from each amendment's EnableAmendment pseudo-transaction on mainnet, in ledgers 85,829,633, 93,814,273 and 95,893,505.

Clawback and No Freeze cannot both be set on the same issuing account. Trying to set one while the other is on fails with tecNO_PERMISSION.

Multi-Purpose Tokens have their own versions of these controls, set per token issuance. There, a "lock" works like a deep freeze, and locking and clawback can be combined.

Related: Individual, global and deep freeze, Clawback and AMMClawback, Check a token's flags first.