Feb. 24, 2026 – Shares of major box makers Smurfit Westrock (SW), International Paper (IP), and Packaging Corp of America (PKG) fell more than 7% on Monday, following a report from JP Morgan highlighting the negative impact of declining U.S. linerboard prices.

The move came after RISI, an industry tracker, reported a $20 per ton month-over-month drop in domestic containerboard prices. JP Morgan called the surprise decline a setback for U.S. box makers, noting that it contrasts sharply with recent price increases announced by most corrugated producers, which ranged $40–70 per ton. The decline was attributed to sluggish demand, discounting, and increased imports of European containerboard.

International Paper, which controls roughly one-third of the North American corrugated packaging market and recently expanded in Europe via the DS Smith acquisition, was among the hardest hit.

Meanwhile, Atlantic Investment Management disclosed it fully exited its position in Graphic Packaging Holding (GPK), selling all 645,584 shares in a transaction worth approximately $12.63 million. GPK shares declined 5.5%.

Retail investor sentiment on Stocktwits showed bearish trends for IP, GPK, and PKG, while SW maintained a neutral stance. Year-to-date, IP shares are up about 11%, PKG 6.5%, SW 16%, and GPK is down nearly 22%.