Arbitrum Token Jumps 135% as Robinhood Chain Booms with $1.02B in Contracts

The Ethereum Layer-2 token market surged in September 2026, with Arbitrum's governance token ARB jumping 135% over the course of the month. This massive gain dwarfed Ethereum's 8% increase during the same period.

The combined market capitalization of major Ethereum Layer-2 tokens rose roughly 65% from their 2026 low to about $11.5 billion by September 22, according to data from CryptoRank reported by CryptoTimes.

The catalyst behind Arbitrum's explosive growth is Robinhood Chain, a network built on Arbitrum Orbit that allows tokenized stocks and ETFs trading with real-time pricing and settlement on Ethereum. Robinhood Chain attracted $146 million in tradeable tokenized stocks before its free-gas promotion expired on September 29.

The revenue from Robinhood Chain flows back to the broader Arbitrum ecosystem through the Arbitrum Expansion Program, which returns 10% of net revenue to the DAO treasury and developer guild. This mechanism is what drives ARB's price, not direct buy pressure from users of Robinhood Chain.