Foreign buyers are holding up the floor under global borrowing costs

The noise is in the auction, the signal is in the buyer

The US Treasury sold 39 billion dollars of 10-year notes at 5.300% on 7 October; according to TFTC, the highest auction yield since November 2000. Headlines read the sale as strong because it stopped 1.7 basis points through the 5.317% when-issued yield. The bid-to-cover ratio of 2.77 beat the 2.52 average of the past 10 auctions, according to RTTNews. The previous month's auction had cleared at 4.834%, so the Treasury's 10-year borrowing cost rose about 47 basis points in 30 days.

The real information lies in the fact that more than 80% of demand came from one group. Indirect bidders, the group that includes foreign central banks and funds, took 80.3% of the paper against a 12-month average of about 71.5%. Primary dealers, the banks obliged to absorb whatever goes unsold, were left with just 2.5%, against an average of around 9.4%. According to Yahoo Finance, the indirect share at the 7-year auction on 24 September was 57.2%, below its 64.6% average. Within two weeks, the world's risk-free floor rested on a 23-point swing in foreign demand.

Why the floor has risen now

In September the Fed voted unanimously to raise rates by 25 basis points to a 3.75–4.00% range; according to Investing.com, its first hike in more than three years. The minutes released on 7 October show most members see one more hike as appropriate by year-end, and FedWatch data cited by Yahoo Finance put the odds of a hike at 17% for October and about 70% for December.

The premise of those minutes went stale within three weeks. September payrolls, released on 2 October, rose by only 29,000 and unemployment climbed from 4.1% to 4.2%. That the 10-year yield held at 5.30% despite weak data suggests the burden has shifted from the policy rate to the term premium, the extra yield investors demand to hold extended-maturity bonds. Supply is feeding that premium: the Treasury is selling a combined 119 billion dollars of 3-, 10- and 30-year paper between 6 and 8 October. According to TFTC, interest outlays hit a record 1.4 trillion dollars in fiscal 2026; that figure is single-sourced and could not be independently verified.

The floor has crossed the Atlantic

The same day, the 30-year gilt yield, the far end of the UK government curve, rose 13 basis points to 6.036%, its highest since January 1998 according to Reuters. For the 10-year gilt Reuters gives 5.48% and Trading Economics 5.4465%; the two sources differ by 3 basis points. Ahead of Chancellor Healey's 28 October budget, Bank of America expects 15 billion pounds of additional borrowing.

In continental Europe, pressure moved on 7 October from sovereign balance sheets to bank balance sheets, and the STOXX Europe Banks index fell 3.5%. Société Générale lost 5.01% and Deutsche Bank 4.94%. France's 10-year yield rose 15 basis points and Italy's 10, while the German Bund was flat. The France–Germany spread is 152 basis points according to Trading Economics and 134.4 according to Ideal Investisseur; the sources differ by 18 basis points. Because banks hold their own governments' bonds, every 10 basis points of spread widening shows up as a hit to capital.

The second round runs from Buenos Aires to Istanbul

Emerging-market dollar debt is priced on top of this floor above 5%. Argentina's country risk, the extra yield its dollar bonds pay over US Treasuries, closed at 586 basis points on 7 October according to Infobae, after an intraday peak of 600. The trigger was the US 10-year touching 5.34% during the session. Adding the 586-point premium to a 5.28% floor puts Argentina's dollar borrowing cost at roughly 11.1%. According to Perfil, the spread hit a year high of 650 on 2 October; the relief that followed Brazil's election lasted less than five days.

In Türkiye the 6 October headline looked positive, with the 5-year CDS falling from 255.69 on 2 October to 247.19 on 6 October, according to Investing.com data. But on the same day France's CDS tightened 10.8% and Brazil's 8.3%; the decline was not specific to Türkiye. The 10-year lira yield stood at 32.75% on 7 October, close to 32.84% on 2 October. The carry trade, foreign money moving from low-yielding currencies into higher-yielding lira assets, has changed direction: non-residents sold 409.9 million dollars of government bonds in the week of 21–25 September.

According to Şeker Yatırım, foreign holdings of Turkish government bonds stand at 17.1 billion dollars, a 6.98% share of the total. For net purchases since the start of the year, Şeker Yatırım gives 2,123 million dollars and Bizim Menkul 1,483.3 million; the two sources differ by 640 million dollars. As the US floor rises to 5.3%, the yield gap foreigners require to accept lira currency risk widens too. For Türkiye, then, the key indicator is not the 5-year CDS but the CBRT's weekly data on bond flows.

What would disprove this reading

Our base case, at 50%, is a floor that stays high but stable: foreign demand at auctions remains above average and the 10-year yield holds in a 5.15–5.45% band. At 30%, foreign demand cracks at one auction, the dealer share passes 15% and the chain spreads to the European periphery and emerging markets. At 20%, weak payrolls pull December hike pricing below 40% and the floor moves lower.

First falsifier: if the indirect share at the November 10-year auction stays above 70% and the dealer share below 10%, the thesis of fragile foreign demand weakens. Second: if FRED's 10-year constant-maturity yield falls below 5.10%, the burden shifts back from the term premium to policy expectations. Third: if foreigners return to net buying of Turkish government bonds in the first two weeks of October, the pass-through from the US floor to Türkiye is limited.