Treasury Doubles Bond Buybacks as $123M ETF Inflow Draws Scrutiny

A record $123 million flowed into a long-duration Treasury ETF the day before the U.S. Treasury doubled its bond buyback program.

The U.S. Treasury said it will at least double buybacks of 10- to 30-year bonds, sending the 30-year yield down 10 basis points to 5.18 percent from near a two-decade high.

The larger operations reflect "consistent strong sponsorship from market participants" in longer-dated sectors, the Treasury said in a statement, citing the significant volume of high-quality offers it routinely receives.

The announcement came a day after a record $123 million flowed into the Pimco 25+ Year Zero Coupon U.S. Treasury Index ETF, which holds STRIPS with an effective duration of about 28 years. Trading volume of 5.2 million shares was nearly double the prior 2024 peak.

The timing has raised questions about whether anyone traded on advance knowledge of the policy. The ETF climbed 3.2 percent Wednesday, its largest gain since November 2024, though it remains down 5.4 percent this year.

A Trade Built for a Yield Shock

The ETF, with about $1.5 billion in assets, is among the most direct ways to bet on long-end rate moves. Zero-coupon STRIPS pay no periodic interest, so their prices swing far more sharply than conventional bonds; a 1 percentage point drop in long-end yields would lift the fund's net asset value by roughly 28 percent.

The inflow landed just as the 30-year yield had climbed to 5.34 percent Tuesday, its highest since 2007, on worries over a deteriorating U.S. fiscal picture and an escalation in the U.S.-Israeli conflict with Iran. A buyer positioned in the ETF stood to capture the full rebound when the buyback news broke.

Buybacks Aim to Ease a Strained Market

The Treasury will raise the maximum size of each buyback operation to at least $4 billion from $2 billion, effective Sept. 9 through Nov. 4. The program lets the government repurchase older, less-liquid "off-the-run" securities from dealers, supporting trading conditions without altering net debt issuance or monetary policy.

The expanded purchases come as U.S. public debt nears $40 trillion and inflation expectations keep long-end yields elevated. Equity futures rose after the announcement, and Bitcoin climbed back above $66,000, as lower borrowing costs supported risk assets.

The pattern echoes earlier episodes that drew scrutiny of Washington trading. Before the Trump administration paused its reciprocal tariffs, options markets showed unusual positioning that prompted broad discussion of possible advance knowledge. Bloomberg has not disclosed the source of the ETF inflows, and no regulator has said it is investigating.

The Treasury is due to publish an updated buyback schedule separately, with the next 10- to 20-year operation set for Sept. 10 and a 20- to 30-year operation on Sept. 24. Whether the expanded purchases can reverse the long end's year-long slide remains an open question, with the ETF still down 5.4 percent in 2026.

Long-duration Treasuries have been the market's most pressured corner this year, with the 30-year yield climbing roughly 100 basis points as investors demanded more compensation for fiscal risk. The buyback expansion offers temporary relief, but traders will watch the Sept. 10 and Sept. 24 operations for signs of whether the support can hold.

This article is for informational purposes only and does not constitute investment advice.