[Standard] Arbitrum Mainnet/Sepolia Nitro Upgrade to v3.9.7

Scheduled for Mar 27, 12:00 - 20:00 UTC

Scheduled

We are upgrading our Arbitrum Mainnet & Sepolia nodes to Nitro v3.9.7. This also includes Robinhood Testnet nodes. During the maintenance window, brief interruptions to RPC availability may occur.

RPC Changes

Legacy receipt queries — fixed Resolved an RLP decoding error affecting historical transactions with legacy Arbitrum receipt encoding. Queries that previously returned errors for older transactions will now return correct results.

https://github.com/OffchainLabs/nitro/releases/tag/v3.9.7

Posted Mar 20, 2026 - 19:57 UTC

This scheduled maintenance affects: Arbitrum (Mainnet Nitro — JSON-RPC API, Mainnet Nitro — WebSocket API, Mainnet Classic — JSON-RPC API, Mainnet Classic — WebSocket API, Mainnet — Webhooks, Mainnet — Streams, Sepolia - JSON RPC, Sepolia - WebSocket API, Sepolia — Webhooks, Sepolia — Streams) and RobinHood (Robinhood Testnet - JSON RPC API, Robinhood Testnet - WebSocket API).