An index fund lends its shares out and takes collateral. The fund's own page, if it mentions this at all, says so in a sentence. What none of them say is who is on the other side.
The filings do say. Item B.4.a of Form N-PORT requires a lending fund to name every borrower, with its legal entity identifier and the amount on loan to it. Read fund by fund that is a footnote. Read the other way round — pivot the whole dataset so the borrower is the row — it becomes a map of who holds American index funds' stock, and the map is small.
742 funds. $175.6 billion on loan. 116 named legal entities. Five firms hold 64.3% of it.
Read from every fund's most recent filing on record · written 2026-09-27 · re-measured as new filings arrive.
By legal entity, as filed
| Borrower, exactly as filed | On loan | Funds it borrows from | Share of all lending |
|---|---|---|---|
| JP Morgan Securities LLC | $28.4bn | 403 | 16.2% |
| Morgan Stanley & Co LLC | $15.6bn | 446 | 8.9% |
| Goldman Sachs & Co. | $13.8bn | 374 | 7.8% |
| Barclays Bank PLC | $13.6bn | 262 | 7.7% |
| BofA Securities, Inc. | $13.3bn | 455 | 7.6% |
| Citigroup Global Markets Inc. | $12.1bn | 416 | 6.9% |
| J.P. Morgan Securities plc | $7.8bn | 95 | 4.5% |
| Morgan Stanley & Co. International plc | $7.4bn | 82 | 4.2% |
| Goldman Sachs International | $6.7bn | 148 | 3.8% |
| BNP Paribas Prime Brokerage International | $6.1bn | 240 | 3.5% |
On this reading the top five entities are 48.2% of all lending and the top ten are 71.1%.
But look at the list again. JP Morgan appears twice. So do Morgan Stanley and Goldman Sachs. The US broker-dealer and the UK entity are separate filers with separate identifiers, and a fund lending to both files two rows.
By the firm behind the entity
Grouping the 116 filed names into the firms that own them:
| Firm | On loan | Share of all lending | Entities it files under |
|---|---|---|---|
| JP Morgan | $36.2bn | 20.6% | 2 |
| Morgan Stanley | $23.0bn | 13.1% | 2 |
| Goldman Sachs | $20.4bn | 11.6% | 2 |
| Barclays | $19.2bn | 10.9% | 4 |
| Bank of America | $14.1bn | 8.0% | 3 |
| Citigroup | $13.6bn | 7.8% | 2 |
| BNP Paribas | $9.4bn | 5.3% | 7 |
| Wells Fargo | $7.6bn | 4.3% | 2 |
| UBS | $5.7bn | 3.2% | 4 |
| Fidelity (National Financial Services) | $3.7bn | 2.1% | 1 |
Top five: 64.3%. Top ten: 87.0%. Against 48.2% and 71.1% when you count the filed names as they come.
One firm — JP Morgan — is on the other side of one dollar in five of all the stock American index funds lend.
BNP Paribas files under seven separate entities and Barclays under four. Neither is doing anything irregular; large banks lend through the branch or subsidiary that suits the jurisdiction. But it means the per-fund table on any single filing understates how concentrated the counterparty side is, and it takes the whole dataset to see that.
One position is a third of the largest borrower's book
JP Morgan's $36.2 billion is spread across 403 funds, which sounds diversified until you look at where it sits:
| JP Morgan's largest single positions | Amount |
|---|---|
| IWM (iShares Russell 2000) | $10.9bn |
| BIL (SPDR 1-3 Month T-Bill) | $2.2bn |
| IJH (iShares Core S&P Mid-Cap) | $1.1bn |
IWM alone is 30% of JP Morgan's entire borrowing across every US fund. That single relationship — one bank, one small-cap fund — is 6% of all securities lending by US-registered funds.
It did not used to be. IWM's largest borrower held 21.3% of its loan book in March 2025 and holds 82.3% now, and the amount grew 8.5-fold in five quarters. That story, quarter by quarter.
And who is supplying it
The borrower side is concentrated. The lender side is the opposite — 742 funds, and the ones doing most of the lending are not the ones you would guess.
By dollars, the big index funds dominate, because they are big:
| Fund | On loan | As a share of the fund |
|---|---|---|
| IWM | $13.30bn | 16.03% |
| VTI | $10.15bn | 0.44% |
| VXUS | $9.95bn | 1.58% |
| IEMG | $7.76bn | 4.79% |
| IJR | $6.02bn | 5.41% |
| IJH | $4.71bn | 3.79% |
VTI lends ten billion dollars and it is less than half a percent of the fund. IWM lends three billion more and it is a sixth of it.
By share of the fund, the list is entirely different:
| Fund | Out on loan | Loan size | Fund size |
|---|---|---|---|
| HYGH | 44.13% | $0.21bn | $0.5bn |
| SMMD | 37.40% | $1.36bn | $3.6bn |
| BYLD | 33.45% | $0.13bn | $0.4bn |
| DWAS | 32.51% | $0.14bn | $0.4bn |
| PRFZ | 31.11% | $0.90bn | $2.9bn |
| KBWD | 29.77% | $0.13bn | $0.4bn |
Not one of them is a household name, and all are small. The pattern holds across the whole dataset:
| Funds | Median share of the fund on loan | |
|---|---|---|
| Over $50bn | 44 | 0.42% |
| Under $2bn | 336 | 1.52% |
| All lending funds | 742 | 1.14% |
A small fund lends about three and a half times as much of itself as a giant one. The mechanical reading is demand: borrowers want what is hard to get, and megacap shares are easy to borrow from a dozen places, while small-cap and niche holdings are not. The filings show the balances and not the reason, so that is a reading and not a finding.
It also explains the IWM number. A small-cap fund with $83 billion in it is an unusual object: the size of a giant, holding the kind of stock that is scarce to borrow. That combination is why one fund is 6% of all lending by US funds.
Why this is worth knowing, and what it does not prove
What it is. Securities lending is how a short seller gets shares to sell, and the fund earns a fee for providing them. It is disclosed, collateralised and entirely ordinary. Every fund here chose to do it.
What concentration means here. If a borrower fails, the fund keeps the collateral and buys the stock back with it. The collateral is what protects the fund, not the number of borrowers. So a concentrated borrower list is not automatically a risk — it is a fact about who the market's demand comes from.
And the collateral figure is only half visible. N-PORT shows collateral the fund holds as a position. Collateral taken in another form does not appear at all. Across the 742 lending funds, 337 report both a loan and cash collateral large enough to compare, with a median cover of 102% — but 96 fall below 95% and 58 more lend materially while reporting almost no cash collateral. Why this site publishes that as a floor and not a verdict.
The firm grouping is ours, not the filings'. The filings give legal entities; the table above maps them onto parent firms by name, which is a judgement. 58 names totalling $8.0 billion are left ungrouped rather than guessed at — including Bank of New York Mellon and Pershing, which are related and are counted separately here. The grouped concentration figures are therefore a floor: grouping more aggressively would raise them, never lower them.
It is a date, not a rate. Loans open and close daily. Every figure is the balance at each fund's most recent filing, and those filings are on different dates, so this is a sum across dates rather than a photograph of one day.
The data
- The dataset, both directions — per fund and per borrower: Who borrows the stock these funds lend
- Every quarter for any fund:
/data/lending/TICKER.json - All funds and all borrowers: /data/lending.json
- Agents can query it directly: the MCP server answers
get_lendingby ticker or by borrower name. - Each borrower total is re-read with a second, independent parser before every deploy; a mismatch stops the release.
Free to reuse under CC BY 4.0.