An MSCI simulation run on May 2026 data flagged Strategy (MSTR) and Metaplanet for removal from the provider's Global Investable Market Indexes under a proposed 50% operating-asset test. Bill Miller IV, chairman and chief investment officer of Miller Value Partners, fired back on September 29, 2026 with a public letter warning the screen could pull Berkshire Hathaway into the same bucket.

Miller's submission arrived one day before MSCI's deadline on its consultation over how to classify "non-operating companies" in its benchmarks. His central argument: a rule built to catch digital-asset treasury companies, or DATCOs, draws a wider net than the provider has publicly acknowledged.

What does MSCI want to change?

MSCI is weighing a two-step test for constituents. The first step asks whether a company's operating assets exceed 50% of its total assets. Firms that fail the screen face demotion out of the standard benchmarks.

The May 2026 simulation named Strategy — the publicly listed vehicle formerly known as MicroStrategy — and Japan's Metaplanet as at risk under the operating-asset threshold. Strategy has significantly outperformed the S&P 500 since adopting a Bitcoin treasury strategy in 2020.

What is Miller's objection?

Miller argues that rigid screens inside a rules-based index could unintentionally shrink the equity opportunity set that passive investors are meant to access. He named Berkshire Hathaway, the holding company run by Warren Buffett, and biotech startups as the kinds of firms that could be wrongly caught by the methodology.

Miller also pressed MSCI to widen the consultation, writing in his letter that "index methodology needs a bigger conversation than a narrow consultation can provide" given the rise of new business models and asset classes.

The practical effect is direct. Tracker funds hold index members automatically; firms that lose benchmark membership surrender the passive flows attached to it.

How did the process get here?

This is MSCI's second attempt at the question. In December 2025, the provider floated a plan that would have removed companies holding more than 50% of their assets in digital assets. MSCI withdrew that proposal in January 2026 and committed to a broader review of how "non-operating" structures fit into its indexes.

The current consultation is the product of that reset. Feedback closed on September 30, 2026, one day after Miller wrote. MSCI has signalled a decision by mid-October 2026, with implementation scheduled for November 2026.

What changes if MSCI proceeds?

The mid-October 2026 ruling will determine whether MSCI absorbs the criticism or carries through with the operating-asset screen largely intact. Either outcome reshapes how global passive money treats Strategy, Metaplanet, and a growing list of copycat issuers.

If the screen survives, expect index-driven rebalancing around the November 2026 implementation window as tracker funds reset their holdings. The corporate-finance consequences extend further: DATCOs typically tap equity markets to fund additional Bitcoin purchases, and a thinner passive-investor base raises the cost of capital for follow-on offerings, complicating the model Strategy has scaled since 2020.

If MSCI softens the approach, it would mark the second time in under a year that industry pushback has reshaped its crypto policy, a precedent that may embolden other issuers lobbying the index provider on methodology.