CooperCompanies stock heads into the open after a 1.5% Nasdaq drop

CooperCompanies stock closed at USD 53.78 on the Nasdaq on September 17, 2026, down 1.5% from the prior close as the shares extended a steep year-to-date decline of about 34% in the latest session. According to data cited by Investing.com and MarketScreener for the September 17, 2026 close, the move left the stock markedly below its levels earlier this year.

September 17, 2026 in numbers

The Cooper Companies Inc. (ISIN US21664P1039, Nasdaq: COO) ended trading on September 17, 2026 at USD 53.78 on the Nasdaq after previously closing at roughly USD 54.61, implying a daily loss of about 1.5% in that session. MarketBeat reported that during trading on September 17, 2026 the shares traded as low as about USD 53.15 and last traded near USD 52.88 before settling, highlighting intraday volatility as investors digested recent developments.MarketBeat MarketScreener’s quote overview for CooperCompanies on September 17, 2026 showed the same closing level of USD 53.78 and a one-week performance figure around minus 1.5%, underlining that the stock lagged broader United States indices over the period.MarketScreener

The reference S&P 500 and Nasdaq Composite indices were broadly stable to slightly weaker over recent sessions, meaning CooperCompanies’ roughly 34% year-to-date decline around the September 17, 2026 close represented a considerable underperformance versus the wider market, as noted in a MarketWatch report on the stock’s trajectory.MarketWatch Earlier in the month, the shares had touched a 52-week low near USD 54.17 following the company’s third-quarter 2026 results and commentary about United States channel inventory reductions, illustrating the stock’s sensitivity to guidance and inventory dynamics.Barchart

Activist pressure and today’s focus

Into today’s session on September 18, 2026, attention centers on activist investor Jana Partners, which has urged CooperCompanies to replace its chief executive and consider potential asset sales, according to a report relaying the contents of a letter sent to the company.Investing.com Seeking Alpha noted that following the Wall Street Journal’s coverage of the activist campaign, CooperCompanies shares rose about 1.7% in post-market trading on September 17, 2026, indicating that investors were reacting to the possibility of strategic changes at the company.Seeking Alpha MarketWatch likewise reported that the stock advanced in after-hours trading on September 17, 2026 after disclosure of Jana Partners’ proposals for leadership and portfolio changes.MarketWatch

GuruFocus highlighted that, as of the September 17, 2026 price near USD 53.77, its GF Value metric suggested that CooperCompanies was trading more than 40% below an estimated intrinsic value, framing today’s session against a backdrop of perceived undervaluation and activist pressure.GuruFocus No specific company earnings release or scheduled results date falls on September 18, 2026 in the latest calendars, so market participants are primarily watching for any response from CooperCompanies to the Jana Partners letter and for further commentary from analysts on governance and strategy as trading resumes today.