BitMine Immersion Technologies (BMNR) has grown its Ethereum ($ETH) reserve from 163,000 tokens in July 2025 to 5,929,198 $ETH as of September 2026, making it the largest Ethereum treasury tracked in the analysis originally published on AMBCrypto. Including the company's other crypto positions and "moonshot" bets, the total treasury is now worth approximately $15.7 billion. At a time when a growing number of public companies have added $ETH to their balance sheets, that scale places BitMine at the top of tracked corporate Ethereum holdings.

A Year of Near-Vertical Growth

The buildup accelerated over the 12-month window, with holdings rising from under one million $ETH in late 2025 to almost six million by September 2026. Measured against the July 2025 starting point, that is a more than thirty-sixfold expansion in a single year.

What the 8-K Reveals

Beyond the headline figure, the company's recent 8-K filing — the form public companies use to disclose material events to the U.S. Securities and Exchange Commission — contains a notable operational change. BitMine has exited its staking agreement with Ethereum Tower, a 10-year deal that carried a revenue-sharing fee tied to net staking income. Staking is how $ETH holders earn rewards for helping secure the Ethereum network, and specialized validators typically charge a fee on those rewards for operating the infrastructure.

In its place, BitMine signed a new contract with American Validator, an Ethereum Tower affiliate. The replacement arrangement reduces the fee to a flat 1.50% of staking rewards on BitMine's staked $ETH. While the change may look modest on paper, the revenue-share fee becomes increasingly consequential as the staked pile grows.

BMNR Stock Momentum Slows

While the treasury has continued to expand, BMNR's share price has cooled. The stock ran from around $18 in mid-August to a high near $27.50 by the end of the month, a stretch during which the Relative Strength Index (RSI), a momentum gauge used to flag overheated moves, moved into overbought territory.

Since that peak, the stock has pulled back to $24.48, with RSI returning to near-neutral levels and the MACD indicator, which tracks trend momentum via moving averages, flattening. The source analysis suggests the market has already priced in much of BitMine's $ETH accumulation and the staking restructuring, describing the current phase as a breather.

Summary

BitMine's $ETH holdings went from 163,000 to 5.93 million in a single year, while BMNR shares have slowed. The company has also simplified its staking economics, moving to a flat 1.5% fee on staking rewards. Because 8-K filings are where material corporate changes surface first, future disclosures are the natural place to track further treasury growth and any new staking arrangements.