Who Has to File a 13F? The $100M Threshold Explained

The trigger: $100 million in Section 13(f) securities

The obligation comes from Section 13(f) of the Securities Exchange Act of 1934, and the test is more mechanical than most people assume. You must file if, on the last trading day of any month in a calendar year, you exercise investment discretion over $100 million or more in "Section 13(f) securities." The SEC publishes an Official List of those securities every quarter. Broadly, it covers US exchange-listed stocks, many ETFs and closed-end funds, certain convertible debt, and listed options on covered names. The SEC's own Form 13F FAQ is the canonical reference and worth reading once in full.

Two phrases in that test do most of the work. First, "investment discretion" means the power to decide what gets bought or sold. Whose money it is does not matter. A manager running $100 million across client separate accounts files. A custodian holding $10 billion with zero discretion does not. Second, the threshold counts only covered securities. A credit fund with $5 billion in bonds and $40 million in listed equities has no 13F obligation at all, and neither does a venture firm whose portfolio is entirely private.

Once you are in, the rhythm is quarterly. Reports are due 45 days after each quarter ends, which for 2026 means February 17, May 15, August 14, and November 16 (the statutory date slides for weekends and holidays; the full calendar with what actually drops on each date is in 13F filing deadlines for 2026).

Who counts as an institutional investment manager

The statutory definition has two prongs. An institutional investment manager is any entity that invests in or trades securities for its own account, or any person (entity or natural person) that exercises investment discretion over someone else's account. That second prong is why the filer population is far more varied than "hedge funds":

Geography is not an escape hatch. A non-US manager that trades covered securities using US means of commerce and crosses the threshold must file too, which is why sovereign wealth funds and foreign banks sit on EDGAR alongside Connecticut hedge funds.

One nuance trips up search queries constantly: funds do not file, managers do. Berkshire Hathaway files a single 13F covering the positions Buffett and his deputies direct (browse it at the Berkshire fund page), and a mutual fund complex files at the adviser level covering every fund it runs. In Arkolith's Q1 2026 dataset, that universe came to 1,824 institutional filers reporting 1.87 million long positions worth $53.7 trillion, all browsable at /investors.

Who does not have to file, and what never shows up

The biggest exempt class is the one people ask about most: natural persons trading their own accounts. An individual with a $900 million personal brokerage account is not an institutional investment manager and files nothing under Section 13(f). Insiders and large owners have entirely separate regimes: Form 4 within 2 business days of a trade, Form 3 within 10 days of becoming an insider, Form 5 within 45 days of fiscal year end, and Schedule 13D within 5 business days of crossing 5% with control intent. The 13F vs 13D vs 13G vs Form 4 guide maps which regime catches which actor.

Below the threshold, everyone is exempt regardless of structure. A 90-million-dollar long/short fund discloses nothing quarterly, and a multi-billion-dollar macro fund holding only futures, FX, and Treasuries may also never file, because none of those are 13(f) securities.

Even for filers, large categories of exposure never appear on the form: short positions, cash, most bonds, foreign-listed shares absent from the Official List, private stakes, and open-end mutual fund shares. A small de minimis carve-out additionally lets filers omit tiny positions that fall under both a share-count floor and a dollar floor. And managers can request confidential treatment to delay disclosure of a position while they build it; the SEC grants this sparingly, but in a few well-known cases very large buyers have kept an accumulation off their public 13F for quarters. Investor.gov has a clean plain-English overview of Form 13F, and the gap between "the filing" and "the portfolio" is the whole subject of how accurate is 13F data.

What happens at the $100 million boundary

The boundary rules surprise people in both directions. Crossing the threshold does not trigger an immediate filing, and dipping back under does not end the obligation.

The test runs on month-ends: if covered securities under your discretion are at or above $100 million on the last trading day of any month during a calendar year, you are in for that cycle. Your first required report covers the quarter ending December 31 of that same year, and you must then file for the first three quarters of the following year even if your assets fall below the line in the meantime.

At the filing itself there are two flavors. A 13F-HR carries the actual holdings table. A 13F-NT is a notice that says "another manager reports my positions," common where discretion is shared between affiliated advisers. This is exactly why naive aggregation across filers double-counts or drops positions, a failure mode covered in how to read a 13F filing.

Compliance at the boundary is imperfect. The SEC has brought enforcement actions against managers that qualified for years and simply never filed, and academic work has generally found that smaller managers near the threshold are the least reliable filers. Treat the filer universe as near-complete for large managers and fuzzier at the edge.

Pulling the filer universe programmatically

If you are building an agent or a screen on top of this data, the filer list is the natural entry point. Arkolith indexes every 13F filer with per-datapoint provenance back to the SEC EDGAR accession number, so an agent can cite the exact filing behind any number instead of inventing one:

# Every institutional filer in the dataset
curl -H "Authorization: Bearer YOUR_KEY" "https://arkolith.com/api/v1/funds"

# Resolve a manager by name
curl -H "Authorization: Bearer YOUR_KEY" "https://arkolith.com/api/v1/search?q=berkshire"

# A filer's reported holdings by CIK
curl -H "Authorization: Bearer YOUR_KEY" "https://arkolith.com/api/v1/funds/0001067983/holdings"

The REST surface takes about two minutes to wire up via the quickstart. If your stack is agent-native, the same data is exposed as MCP tools, and connecting market data to Claude over MCP walks through that path end to end. Either way you inherit the threshold logic described above: what you query is what 1,824 managers were legally required to disclose, nothing more.

Frequently asked questions about who has to file a 13F

Does an individual investor ever have to file a 13F?

Not for their own money. A natural person trading a personal account is not an institutional investment manager at any size. The exception is a person who exercises investment discretion over other people's accounts above the $100 million threshold, which makes them a manager in the statute's eyes.

Do hedge funds under $100 million have to file 13Fs?

No. The obligation only attaches once covered securities under discretion reach $100 million on a month-end, and the test counts only Section 13(f) securities. A sub-threshold fund, or a large fund holding mostly futures, bonds, or private assets, files nothing.

Do foreign investment managers have to file a 13F?

Yes, if they trade covered US securities using US means of interstate commerce and cross the threshold. The rule attaches to the activity, not the manager's domicile, which is why sovereign wealth funds and non-US banks appear among EDGAR's 13F filers.

Can a manager stop filing once it falls below $100 million?

Not immediately. Once the month-end test is met, the manager must file for the December quarter of that year plus the first three quarters of the next year, regardless of asset declines. The obligation only lapses after a full calendar year in which no month-end touches $100 million.

This article explains public filings and data concepts. It is not investment advice.