Wall Street ended a three-day losing streak on Wednesday after the US Treasury Department moved to steady a bond market that had pushed long-dated yields to their highest levels in nearly two decades. The dollar fell to its weakest level in about three months, while equities posted a broad, though uneven, advance into the close.

The Treasury said it would more than double the size of its buybacks of longer-dated government debt, lifting the maximum from $2 billion to at least $4 billion. The operations will target the 10- to 20-year and 20- to 30-year portions of the curve. The move came after weeks of pressure in that part of the market, where 30-year Treasury yields climbed to around 5.19% to 5.21%, the highest level since 2007.

Following the announcement, yields fell 8 to 9 basis points, easing some of the strain on a market that had effectively seen a buyers' strike on longer maturities since late June. The decline in yields also fed through to currency markets, sending the US dollar to its weakest point in roughly three months.

Equities took their cue from the bond market rather than the Federal Reserve minutes, which had been hawkish. The Dow Jones Industrial Average and the S&P 500 each closed about 0.2% higher, while the Nasdaq Composite added roughly 0.16%, according to Yahoo Finance. For investors, the contrast underscored how moves in Treasury markets can quickly filter into stocks and currencies, especially when borrowing costs at the long end are already elevated.

The gains were not evenly distributed. Moderna was the session's standout performer, with shares surging as much as 176% after the company reported positive results from a late-stage melanoma vaccine trial developed with Merck. Merck shares also rose sharply on the news.

Chip stocks, by contrast, remained a laggard. The sector stayed under pressure from elevated yields and continuing investor concern about the scale of capital spending tied to artificial intelligence infrastructure, even as the broader market firmed. The Treasury's announcement did not ease those concerns.

Adding to the semiconductor-sector news flow, South Korea's SK Hynix announced that it would buy back and cancel roughly $28.6 billion worth of treasury shares as part of its 2025 to 2027 capital return plan. The company said it intends to return at least half of the free cash flow generated over that period to shareholders.

The announcement provided a rare positive catalyst for chip sentiment on a day when the group otherwise lagged the wider market. Traders will now be watching whether the Treasury's intervention is enough to keep long-end yields contained, while also tracking how the market absorbs a heavier buyback program in the same long-dated maturities that have been under the most pressure since late June.

Giuseppe highlighted the move as it unfolded:

US Treasury is increasing the size of liquidity support buyback operations for longer-dated securities