Tepid investor demand and elevated valuation concerns have driven a slowdown in U.S. IPO activity during the fourth quarter of 2026, with multiple high-profile deals postponed amid mixed post-listing performance. Recent pricings, including Accelevation Holdings on September 29 and ADARx Pharmaceuticals on September 24, reflect selective appetite, while companies such as Oura, EG Group, and SB Energy have delayed plans into 2027. Market focus has shifted to Anthropic’s anticipated mid-November debut after the U.S. midterms, with OpenAI pushed further out. Over 250 U.S. IPOs have priced year-to-date through early October, though trading volumes and aftermarket returns remain uneven against broader equity benchmarks and Treasury yield levels. Key near-term catalysts include any updated Anthropic S-1 details and potential filings from eligible names like Nscale.