Aptos launches Encrypted Mempool: How does it work?

Aptos has launched its Encrypted Mempool feature on mainnet, allowing users to hide pending transaction details until validators finalize their order, as its native APT token fell more than 11% over 24 hours.

Aptos confirmed the October 12 launch, saying the optional feature was designed to protect traders from frontrunning, sandwich attacks and other forms of maximal extractable value (MEV). The system encrypts transaction contents before they reach the network, preventing validators and outside observers from viewing the instructions while transactions await ordering. Once a block is finalized, validators collectively decrypt its contents and execute the transactions.

Aptos Encrypted Mempool hides pending trades from bots

Through the new feature, users can encrypt transaction instructions before submitting them to the Aptos blockchain. Details such as the assets involved, transaction amounts and smart contract functions remain hidden while validators determine the order in which transactions will execute. The sender’s wallet address and network fee remain visible throughout the process.

Aptos explained that trading bots often monitor pending blockchain transactions to identify profitable opportunities before execution. Some attempt to place trades ahead of large orders, while others execute transactions before and after a user’s trade to profit from the resulting price movement.

In its announcement, Aptos warned that “Bots use that visibility to trade against you or copy your strategy.” The network said Encrypted Mempool was developed for institutional traders handling large transactions, individual users seeking protection against MEV attacks, automated trading agents and blockchain application developers.

The project described the feature as a protocol-native implementation that uses the existing Aptos validator network for both transaction ordering and decryption. Unlike systems relying on external committees or private transaction builders, the new mechanism operates through validators already responsible for securing the blockchain.

Aptos had previously outlined its plans to protect transactions from frontrunning in May 2026, when it described the proposed technology and its intended use in institutional trading. The October launch confirms that the feature has moved from development into mainnet operation.

Encrypted transactions require higher gas fees

Under the new system, a compatible wallet encrypts transaction instructions on the user’s device before sending them to the network. Validators then agree on the transaction order without knowing the hidden contents. After block consensus is completed, they combine their decryption shares to reveal and execute the transactions.

Aptos said no individual validator can independently decrypt a pending transaction. Its encryption model requires a stake-weighted validator majority, following the security assumptions used by the blockchain’s existing consensus mechanism. The implementation is described in AIP-144, the network’s technical proposal for encrypted transaction processing.

According to the project’s developer documentation, encrypted transactions must pay a minimum gas price of 200 octas per gas unit, twice the network’s base minimum. Each transaction incurs an extra 375 gas units for decryption, separate from the gas consumed by executing its instructions.

The network reported approximately 20 milliseconds of additional latency per block during tests involving 50 nodes. Aptos said the result was measured against its production AptosBFT consensus implementation, which normally finalizes blocks in less than one second. The encryption system underwent an independent security review by ZKSecurity before launch.

For developers, Aptos has introduced encrypted transaction support through version 7.0.0 and later of its TypeScript software development kit. Existing Move smart contracts do not require modifications to support the feature. Petra is the first wallet to offer encryption directly within its transaction signing process, while Aptos-based perpetual futures exchange Decibel plans to use it for private pending orders.

Aptos targets sandwich attacks that have cost traders millions

The launch follows research documenting the financial losses associated with automated transaction manipulation across blockchain networks. In a sandwich attack, a bot identifies an incoming trade, buys the targeted asset before the user’s transaction executes and sells afterward at a higher price.

Blockchain analytics company Bitquery identified approximately 6.9 million sandwich attacks on Solana between October 30, 2025, and October 7, 2026. Its investigation found that 2,545 bot wallets targeted approximately 2.2 million wallets during the 11-month period, extracting $29.7 million before trading costs.

According to Bitquery, roughly 96% of the identified attacks involved memecoins traded through Pump.fun-related markets. The daily number of recorded attacks increased from approximately 3,400 in late 2025 to 51,900 in September 2026. The research covered Solana transactions and did not establish equivalent losses on Aptos.

Other blockchain projects have introduced different approaches to transaction protection. Ethereum’s Flashbots Protect directs transactions through private infrastructure, while Gnosis Chain uses Shutter’s encrypted mempool technology. Aptos said its implementation differs because the existing validator set handles both transaction ordering and decryption.

Alongside Encrypted Mempool, the network offers Keyless Accounts and Confidential APT as separate optional privacy features. The first addresses account access, while Confidential APT conceals eligible transfer amounts. Encrypted Mempool focuses on hiding transaction instructions before execution, with completed transaction information remaining publicly auditable.

APT price falls below $0.80 despite mainnet launch

Following the launch, APT remained under selling pressure, trading at $0.7995, down 11.5% over 24 hours. According to CoinGecko, the token moved between $0.7974 and $0.9135 during the period, while trading volume stood near $98.91 million. Its market capitalization was approximately $697.14 million at the time of the price check.

The latest decline contrasts with the earlier daily chart reading supplied for APT, which showed a 4.47% gain at $0.8290. Technical indicators from that chart placed the 20-day simple moving average at $0.8166, with Bollinger Band resistance near $0.8970 and the lower band at $0.7361. Those readings describe the earlier chart and should not be treated as updated indicators for the latest price.

Meanwhile, the earlier Relative Strength Index reading of 54.87 suggested moderately positive momentum before the latest decline. The RSI remained below its signal average of 57.25, indicating weaker buying momentum at that observation point. APT’s subsequent move below $0.80 placed the token beneath the earlier 20-day moving average, although a new indicator calculation would be required to confirm its current technical position.

In May, Aptos Foundation and Aptos Labs committed more than $50 million toward ecosystem development involving trading infrastructure, AI agents and blockchain research. The initiative includes Decibel and Shelby, with the organizations supporting financial applications and automated systems built on Aptos.

The project said Decibel had exceeded $1 billion in cumulative trading volume during its development, while Shelby was being built for data-heavy applications. Under the newly released Encrypted Mempool system, Aptos confirmed that Decibel will use encrypted transactions to conceal order details until execution, with Petra providing users an option to enable encryption while signing transactions.