Aptos activated an opt-in Encrypted Mempool on its mainnet on October 12, following governance approval of AIP-144. The feature allows users to keep pending transaction details hidden from trading bots until the block is finalized, reducing frontrunning and sandwich attacks tied to maximal extractable value (MEV).
In the new design, compatible wallets encrypt transaction payloads on the sender’s device before submission. Validators order blocks without seeing the called function, input parameters, asset types, or transfer amounts, while sender addresses and network fees remain visible. Once a block reaches finality, the validator set collectively decrypts the batch using a stake-weighted threshold, meaning no single validator can read pending transactions alone.
Aptos reported roughly 20 milliseconds of added latency per block in a 50-node test environment, within its sub-second AptosBFT finalization window. Encrypted transactions must pay at least 200 octas per gas unit, double the base minimum, and use an additional 375 gas units for decryption. ZKSecurity completed an independent security review ahead of the mainnet deployment.
Petra is the first wallet to integrate the encryption option directly into its signing flow, while Decibel plans to use encrypted transactions for private pending orders. Developer support ships in version 7.0.0 and later of the Aptos TypeScript SDK, with no changes needed for existing Move smart contracts. However, keyless signers and account abstraction signers are not yet supported.
Aptos framed the upgrade as a native counter to automated extraction, stating that bots use pending visibility “to trade against you or copy your strategy.” The system provides payload privacy rather than transaction anonymity, concealing trade intent but not participant identity.
The launch arrives as Bitquery data covering roughly 11 months through early October 2026 recorded about 6.9 million sandwich attacks on Solana, extracting $29.7 million before trading costs from around 2.2 million wallets. About 2,545 bot wallets were involved, and roughly 96% of attacks involved Pump.fun-linked memecoins.
According to CoinGecko, APT traded at $0.7995 after the launch, down 11.5% over 24 hours, with volume near $98.91 million and a market capitalization of about $697.14 million.
