UAO Research · May 2026 · Stewardship & Governance · A Universal Asset Owners special report
If you own a slice of the entire market, you cannot sell your way out of a bad system — you can only try to fix it from the inside. That is the theory of stewardship for a universal owner. The practical question is whether it works. The concentration of ownership in a handful of large institutions is now historically unprecedented: the "Big Three" index managers — BlackRock, Vanguard and State Street — are the largest single shareholder in roughly 88% of S&P 500 companies and cast about a quarter of the votes at those companies' meetings (Big Three Power, and Why It Matters, Harvard Law School Forum on Corporate Governance.). On paper, that is enormous influence. Whether it is being used — and whether it should be — is one of the most contested questions in corporate governance.
What the evidence says
The mechanical case for universal-owner stewardship is strong. A diversified owner internalises economy-wide externalities: if one portfolio company's behaviour lowers the value of many others, the owner pays for it across the book, so it has a direct financial interest in reducing system-level harm. Because index owners cannot exit a holding without abandoning the index, engagement and voting are their only levers — which, some scholars argue, gives them stronger incentives to use those levers than a trader who can simply sell (Hidden power of the Big Three? Passive index funds, re-concentration of corporate ownership, and new financial risk, Business and Politics (Cambridge).).
The evidence on how that power is actually exercised is more sobering. The Big Three collectively manage over $30 trillion, but they vote with company management in roughly 90% of resolutions and against most shareholder proposals — a posture that looks far more deferential than the "owners of corporate America" framing implies. Active stewardship is concentrated among a smaller set of mission-driven owners — funds like Norway's NBIM, which publishes its voting intentions in advance, and large public pensions that run focused engagement programs — rather than spread evenly across all the capital that, in theory, has the standing to act.
Where it is contested
There is no consensus that universal-owner stewardship is desirable or even legitimate. One critique, from the political left, is that the Big Three's deference means concentrated ownership delivers little real accountability. A second, from the political right, is the mirror image: that coordinated investor influence on issues beyond financial return is an overreach that should be reined in, an argument now playing out in US legislatures and litigation. A third, more technical critique questions the resourcing — whether any manager can meaningfully steward tens of thousands of holdings — and the common-ownership concern that the same investors holding competing firms could blunt competition. The result is a genuine standoff: the legal and political latitude for systematic stewardship is contracting at the very moment the ownership concentration that enables it has peaked.
From the allocator's seat
For an asset owner, the realistic posture is to treat stewardship as a scarce resource to be spent where it can move a systemic dial, not as a blanket obligation. That means prioritising the handful of economy-wide risks the fund genuinely cannot diversify away — climate transition, financial stability, governance quality — and concentrating engagement and voting there, rather than diffusing effort across every holding. It means deciding deliberately whether to vote in-house or delegate, given that delegated voting has tended toward management deference. It means coalition-building, since a single owner rarely has the votes alone, while being clear-eyed about the legal and antitrust limits on coordination. And it means measuring and disclosing stewardship outcomes, because in the current political environment a universal owner's licence to engage depends on showing the activity is tied to long-term value, not to a political agenda.
What to watch next
Watch voting policy at NBIM, CPP Investments and the large index managers — any shift toward or away from management deference is a leading indicator. Watch US legislation and litigation on investor coordination and proxy advice, which is redrawing the legal boundary in real time. Watch the next proxy season's support levels for environmental and governance proposals. And watch whether any major owner adopts an explicit, methodology-backed systematic-stewardship framework — the move that would turn the theory into a governable program.
Sources
- Big Three Power, and Why It Matters, Harvard Law School Forum on Corporate Governance, 2022.
- Hidden power of the Big Three? Passive index funds, re-concentration of corporate ownership, and new financial risk, Business and Politics, Cambridge University Press.
- Universal Owners, Shareholder Primacy, and Stakeholderism, Emory Corporate Governance and Accountability Review.
UAO Research. AI-assisted monitoring and drafting; reviewed and edited by the UAO editorial desk before publication. Not investment advice.