Notice: Editorial analysis that does not constitute financial advice or a recommendation regarding any asset or entity. Positions, counterparties, clearing routes, and collateral are derived from the fourteen monthly N-MFP3 filings of the Circle Reserve Fund series presented by BlackRock Funds in EDGAR (CIK 844779), for closings from August 31, 2025, to September 30, 2026, filed on October 14, 2026; USDC in circulation, reserves, and repo via the other route are from Deloitte's attestations for Circle from June to August 2026. The form publishes each position separately: totals, percentages of equity and portfolio, sums by group, collateral distribution, cleared share, series, and turnover are CleanSky calculations and are marked as such. Without a September 30 attestation, the ratios relative to USDC for that closing use DefiLlama, an aggregator. CleanSky does not receive commissions or referral payments from Circle, BlackRock, or any named entity.
Two documents describe the same portfolio with the same figure to the dollar —$49,584,000,000 in repo as of August 31, 2026— and only one of the two provides the names of the counterparties. The Deloitte attestation that Circle publishes every month summarizes that repo in a single line: overnight cash loans to global financial institutions, overcollateralized with Treasury debt. The N-MFP3 form that BlackRock files in EDGAR for the same fund, the Circle Reserve Fund, breaks it down position by position with the counterparty, LEI, clearing house, and collateral with its maturity. As of September 30, 2026, that repo totals $36,654 million, representing 58.68% of equity and 59.10% of the portfolio —CleanSky calculation based on the form— across fifteen lines with thirteen legal entities and twelve banking groups. 91.12% is cleared through FICC, so the majority legal counterparty is the clearing house and not the bank. What remains after granting this are names that repeat for fourteen consecutive months and collateral of which 96.81% matures in more than one year.
These are three layers over the same dollar. Circle's Q2 2026 10-Q describes the fund in one sentence —bills at three months or less, overnight repo on Treasury debt, and cash— and figures its portion at $61,900 million as of June 30, 2026. The monthly attestation breaks it down into figures: USDC in circulation, reserves, CUSIP-by-CUSIP bills, and the repo in one line. The N-MFP3 drills down to counterparties, and it is the layer that Circle does not present.
How much repo does the Circle Reserve Fund declare as of September 30, 2026?
Net equity as of September 30, 2026, is $62,467,425,771.89, with $1,003,847,741.05 in cash and a portfolio of $62,015,578,415.09, with a weighted average maturity of 17 days published by the SEC form itself. Inside, there are 31 positions: sixteen Treasury bills for $25,361.6 million, maturing between October 1 and December 31, 2026, and fifteen repo lines for $36,654 million, all maturing on October 1 and all tripartite. The breakdown between the two classes is a CleanSky calculation: the form numbers positions without grouping them.
That this breakdown describes the actual portfolio backing USDC is proven by the reconciliation with the other primary source. The Deloitte attestation for the August 31, 2026 closing declares $49,584,000,000 of repo in the fund; the sum of the twelve repo lines in the N-MFP3 for that closing yields $49,584,000,000. Zero difference. As of July 31, 2026, $52,723,000,000 via both routes; as of June 30, $52,527,000,000. Equity matches except for rounding to the dollar: the $62,317,374,425 from the August attestation versus the $62,317,374,427.07 in the netAssetOfSeries field—a two-dollar difference because the attestation sums rounded components. The sums are CleanSky calculations.
| Monthly Closing | USDC in Circulation ($) | Total Reserves ($) | Circle Reserve Fund ($) | Repo: Deloitte Attestation ($) | Repo: N-MFP3 Sum ($) | Difference |
|---|---|---|---|---|---|---|
| Jun-30-2026 | 73,268,560,097 | 73,344,909,176 | 61,917,347,895 | 52,527,000,000 | 52,527,000,000 | 0 |
| Jul-31-2026 | 71,826,453,410 | 71,904,101,332 | 60,717,246,965 | 52,723,000,000 | 52,723,000,000 | 0 |
| Aug-31-2026 | 73,320,757,305 | 73,398,532,613 | 62,317,374,425 | 49,584,000,000 | 49,584,000,000 | 0 |
Using the two primary sources from the August 31, 2026 closing, the fund represents 84.90% of USDC reserves and its repo is equivalent to 67.63% of USDC in circulation, a CleanSky calculation based on the attestation. There is no attestation for September 30 —empty link on Circle's transparency page as of October 14, 2026— and the only denominator is from DefiLlama, $74,583,471,121, an aggregator: with it, the repo would be 49.14% and the five banks 36.99%.
Searching for "Circle Reserve Fund" in the EDGAR company search returns empty, verified on October 14, 2026: the fund is a registered series (S000077205) within BlackRock Funds and the form is found via the registrant's CIK 844779 or through full-text search. The September closing form was filed on October 7, 2026.
Is FICC the legal counterparty for the repo backing USDC?
Mostly, yes. Of the $36,654 million in repo at the September 30, 2026 closing, $33,400 million —91.12% of the repo and 53.47% of equity, CleanSky calculation— are declared with the central clearing indicator active and Fixed Income Clearing Corporation (FICC) as the clearing house. In a sponsored repo, the bank acts as the Sponsoring Member and introduces the fund as a Sponsored Member; the transaction is novated to the clearing house, which becomes the central counterparty for both legs. In this route, the entity facing the fund is FICC. The Sponsored Service operated by DTCC reported more than 2,900 sponsored members and an average daily volume of $2.3 trillion with data from the second quarter of 2026. This novation and the sponsoring member's guarantee to the clearing house are described in the SEC notice on rule SR-FICC-2019-007, from January 2020.
That granted, the Circle Reserve Fund form still reveals three things.
- The bank is the one providing the collateral and the one Item C.1 of the N-MFP3 requires to be named as the counterparty, with its LEI, whether the transaction is cleared or not.
- $3,254 million of the repo at the September 30, 2026 closing does not have a clearing house behind it. This represents 8.88% of the repo and 5.21% of equity —CleanSky calculation— distributed, in millions of dollars, among JP Morgan Securities (2,984), Nomura Securities International (250), Wells Fargo Securities (10), and Citigroup Global Markets (10). The $3,043.7 million in collateral backing the JP Morgan Securities line matures between 2028 and 2032.
- In both routes, what protects the Circle Reserve Fund is the collateral. Counterparty risk —the risk that the party on the other side of a transaction does not return what was promised— explained from scratch is managed in repo by delivering securities worth more than the cash lent, and the form publishes these securities one by one with CUSIP and maturity.
A reading note: the cleared share jumps from 81.07% of the repo at the June 2026 closing to 17.73% in July, to 0.00% in August, and to 91.12% in September. The form does not distinguish a real migration away from the clearing house from a change in how Items C.1 and C.8.b are filled out, so no claims are made regarding July and August.
Which repo counterparties does the Circle Reserve Fund declare in the N-MFP3 as of September 30, 2026?
Thirteen legal entities with distinct LEIs, twelve banking groups, fifteen lines. The three figures are not interchangeable: there are two entities from the Wells Fargo group and there are counterparties with two lines. The four largest entities account for 38.02% of equity at that closing —CleanSky calculation with equity as the base; based on the portfolio, it yields 38.30%—.
| Counterparty declared in Item C.1 (Sep-30-2026 closing) | Repo Value ($M) | % of Equity | % of Repo | Declared Route | Collateral ($M) |
|---|---|---|---|---|---|
| Wells Fargo Bank NA | 6,959.0 | 11.14 % | 18.99 % | FICC | 7,098.2 |
| Goldman Sachs & Co LLC | 6,190.0 | 9.91 % | 16.89 % | FICC | 6,313.8 |
| Barclays Bank PLC | 6,100.0 | 9.77 % | 16.64 % | FICC | 6,222.0 |
| BNP Paribas SA | 4,500.0 | 7.20 % | 12.28 % | FICC | 4,590.0 |
| Citigroup Global Markets Inc | 3,830.0 | 6.13 % | 10.45 % | 3,820.0 FICC + 10.0 bilateral | 3,906.6 |
| Mizuho Securities USA LLC | 3,819.0 | 6.11 % | 10.42 % | FICC | 3,895.4 |
| JP Morgan Securities LLC | 2,984.0 | 4.78 % | 8.14 % | bilateral | 3,043.7 |
| Deutsche Bank AG | 800.0 | 1.28 % | 2.18 % | FICC | 816.0 |
| Crédit Agricole CIB (New York Branch) | 711.0 | 1.14 % | 1.94 % | FICC | 725.2 |
| BofA Securities Inc | 500.0 | 0.80 % | 1.36 % | FICC | 510.0 |
| Nomura Securities International Inc | 250.0 | 0.40 % | 0.68 % | bilateral | 255.0 |
| Wells Fargo Securities LLC | 10.0 | 0.02 % | 0.03 % | bilateral | 10.2 |
| Natixis SA | 1.0 | 0.00 % | 0.00 % | FICC | 1.0 |
Overcollateralization is 2.00% across all lines for that closing except for Natixis, at 2.01%: $37,387.1 million in guarantees against $36,654 million lent. Tether's quarterly attestation with KPMG publishes asset categories without counterparty names for its repos: the level of detail for the two largest digital dollars is not comparable.
Have five banking groups sustained the Circle Reserve Fund's equity since August 2025?
Wells Fargo, Goldman Sachs, Barclays, BNP Paribas, and Citigroup appear in all fourteen monthly reports since the August 31, 2025 closing, and their sum has been between 44.17% and 72.08% of equity in all of them. The series and the sums by group are CleanSky calculations and depend on an assumption of ours: until the July 2026 closing, the fund declared sponsored repo with the issuer "Fixed Income Clearing Corporation" plus a suffix (BNP, CITI, GS, WFBK, BARCLAYS BANK PLC) and the clearing house's LEI, and since September it declares the bank with the clearing house as the central counterparty. Mapping each suffix to its group and summing the two Wells Fargo entities is a CleanSky convention; without it, the series by bank does not exist.
| Monthly Closing (N-MFP3) | Equity ($M) | Repo ($M) | Repo / Portfolio | Five Banks / Equity | Collateral > 10 Years | Collateral ≤ 1 Year |
|---|---|---|---|---|---|---|
| Aug-31-2025 | 61,015.0 | 36,906.0 | 60.19 % | 49.58 % | 14.20 % | 0.83 % |
| Sep-30-2025 | 64,165.2 | 41,619.0 | 65.67 % | 55.22 % | 33.24 % | 2.59 % |
| Oct-31-2025 | 66,065.7 | 40,196.0 | 59.94 % | 52.15 % | 42.53 % | 2.73 % |
| Nov-30-2025 | 65,966.3 | 40,649.0 | 62.38 % | 56.50 % | 37.04 % | 10.83 % |
| Dec-31-2025 | 66,316.6 | 50,790.0 | 77.24 % | 67.18 % | 39.86 % | 2.18 % |
| Jan-31-2026 | 59,817.0 | 40,199.0 | 68.12 % | 59.05 % | 51.69 % | 3.79 % |
| Feb-28-2026 | 64,767.0 | 44,571.0 | 68.56 % | 60.86 % | 35.23 % | 3.23 % |
| Mar-31-2026 | 66,467.0 | 40,756.0 | 62.06 % | 53.77 % | 30.39 % | 3.15 % |
| Apr-30-2026 | 66,367.1 | 46,998.0 | 71.09 % | 65.21 % | 20.43 % | 8.27 % |
| May-31-2026 | 65,167.2 | 45,171.0 | 67.19 % | 60.12 % | 29.27 % | 10.70 % |
| Jun-30-2026 | 61,917.3 | 52,527.0 | 86.04 % | 68.78 % | 26.70 % | 5.73 % |
| Jul-31-2026 | 60,717.2 | 52,723.0 | 88.02 % | 72.08 % | 40.28 % | 5.72 % |
| Aug-31-2026 | 62,317.4 | 49,584.0 | 80.62 % | 69.26 % | 19.00 % | 2.11 % |
| Sep-30-2026 | 62,467.4 | 36,654.0 | 59.10 % | 44.17 % | 27.90 % | 3.19 % |
The September 30, 2026 closing marks the fourteen-month low in the two columns that matter: 59.10% repo over portfolio and 44.17% for the five banks over equity, the data point that most challenges the idea of persistence. At the same time, 44.17% of a $62,467.4 million fund is $27,589 million across five banking groups, and the number of counterparties for that closing is the highest in the series: thirteen entities compared to the nine to eleven in the five 2025 closings.
Repo over portfolio never dropped below 59.10% nor exceeded 88.02%, and collateral maturing in more than ten years moved between 14.20% at the August 2025 closing and 51.69% in January 2026. Collateral maturing in one year or less did not exceed 10.83% in any of the fourteen closings: the short end of the curve is the smallest slice of the guarantee every month.
What collateral does the Circle Reserve Fund receive for its repo as of September 30, 2026?
US Treasury debt with long maturities. The distribution by residual maturity of the collateral for the fifteen lines at the September 30, 2026 closing, a CleanSky calculation based on the CUSIPs published in the form, leaves 3.19% at one year or less and 96.81% above one year.
| Residual Maturity of Repo Collateral (Sep-30-2026 closing) | % of Collateral |
|---|---|
| One year or less | 3.19 % |
| One to five years | 52.95 % |
| Five to ten years | 15.95 % |
| More than ten years | 27.90 % |
| Overcollateralization on cash lent | 2.00 % |
The distance between the two halves of the portfolio is a comparison of dates. The sixteen bills owned by the fund mature between October 1 and December 31, 2026: three months at most. Of the guarantee received for the repo, 27.90% matures in more than ten years, and the $3,043.7 million backing the JP Morgan Securities bilateral line matures between 2028 and 2032.
If the Circle Reserve Fund had to keep the guarantee, what would enter the balance sheet does not mature in December, and its sale value would depend on the interest rate of the day. Overcollateralization remains between 1.97% and 2.03% of the cash lent in thirteen of the fourteen closings.
Why doesn't SEC Rule 2a-7 force the Circle Reserve Fund to diversify repo by counterparty?
Because the rule does not look at the bank. Section (d)(3)(ii)(A) of 17 CFR 270.2a-7 allows treating the acquisition of a fully collateralized repo as if it were the acquisition of the underlying securities, and the 5% limit per issuer in (d)(3)(i)(A)(1) then applies to the issuer of the collateral, here the US Treasury. A fund with 11.14% of its equity facing a single counterparty declared in Item C.1 complies with the regulation as written: nothing in that portfolio is irregular.
What exists is a gap between the three layers. The rule applies the issuer limit to the collateral and leaves the counterparty uncapped. The attestation publishes the repo total with its wording on overcollateralized overnight lending, without asking for the name. The form does ask —Item C.1 for the counterparty, Item C.8.b for the clearing house— but it is filed elsewhere, by another registrant, and for another purpose: money market fund supervision. The framework of Rule 2a-7 and the Deloitte attestation surrounding USDC is what distributes the data this way.
What changed in the Circle Reserve Fund's portfolio between July 31 and September 30, 2026?
Two months of heavy turnover, with no declared reason. Repo fell by $16,069 million —a 30.48% drop, CleanSky calculation based on the two forms—, bills rose by $18,182 million, and equity rose by $1,750 million: the fund went from the series high in repo over portfolio to the low in two reports.
| Concept | Jul-31-2026 Closing | Sep-30-2026 Closing | Change |
|---|---|---|---|
| Overnight Repo ($M) | 52,723.0 | 36,654.0 | −16,069.0 (−30.48 %) |
| Treasury Bills ($M) | 7,179.1 | 25,361.6 | +18,182 |
| Net Equity ($M) | 60,717.2 | 62,467.4 | +1,750 |
| Repo / Portfolio | 88.02 % | 59.10 % | −28.92 percentage points |
| Five Banks / Equity | 72.08 % | 44.17 % | −27.91 points |
A price data point accompanies the movement without explaining it. At the September 30, 2026 closing, the sixteen bills yield a size-weighted 3.966% and the fifteen repo lines 3.886%: eight basis points in favor of owned debt, with both weighted yields calculated by CleanSky based on each position in the form BlackRock presents to the SEC. The form does not declare anyone's intent, and the turnover remains as context. The map of the Fed hike passthrough to on-chain dollar rates covers the same quarter, as does Circle and Tether's interest rate exposure, the fund's weight in the issuer's income statement.
Which October 2026 N-MFP3 would disprove that five banks sustain the USDC reserve fund?
Three claims with a threshold and a single date: the October closing form arrives at the latest by the fifth business day of November, November 6, 2026, per the 17 CFR 270.30b1-7 deadline. With that report in hand, each is either confirmed or debunked.
| Claim | Threshold that withdraws it (October 2026 closing, pub. limit Nov-6-2026) | Where to verify |
|---|---|---|
| Five banking groups persistently sustain the fund's equity | Five banks below 30% of equity, or repo below 40% of the portfolio | October N-MFP3: Item C.1 and series equity |
| Repo collateral is structurally long | Collateral > 10 years below 10%, or collateral ≤ 1 year above 50% | October N-MFP3: line-by-line collateral |
| The attestation publishes the repo total and no counterparty names | Circle's September attestation or the fund's holdings file naming counterparties | circle.com/transparency and the fund's factsheet at blackrock.com |
Until then, what is evaluable with the two primary sources is concrete: repo matches to the dollar in the June, July, and August 2026 closings between the Deloitte attestation and the BlackRock form; as of September 30, 2026, it is $36,654 million with thirteen named counterparties and 91.12% cleared at FICC; five banking groups have accounted for between 44.17% and 72.08% of equity over fourteen closings; and 96.81% of collateral matures in more than one year. Why the fund rotated $16,069 million in two months is not answered by any of the three layers.