The simplest mental model for how MEV protection actually works.
The public mempool is a shop window: every pending transaction is visible to bots before it’s mined. A private mempool skips the window — your transaction goes directly to block builders, so there’s nothing for sandwich bots to see. Some services then auction the harmless back-run value back to you.
A private mempool that adds a searcher auction paying up to 90% back to you.
A stricter version: encrypts your transaction so not even the builder sees your intent early.
A private mempool removes your transaction from public view; an encrypted mempool (Shutter) hides its contents entirely until it’s included.