** Shares in Syensqo SYEN.BR drop 20%, on track for worst day ever, after the specialty chemicals maker posted what J.P. Morgan calls a "very weak" 2026 guidance
** The group now sees 2026 underlying EBITDA of 1.1 billion euros ($1.3 billion), compared to the 1.29 billion euros expected on average by analysts
** "Even adjusting for FX headwind which may not have been fully captured in consensus estimates, FY26 adj EBITDA guidance... implies 4% organic EBITDA decline in FY26 on a weaker FY25 base," JPM says
** The broker adds most investors expected some growth in FY26 on the back of Syensqo's significant exposure to aerospace and defence segments
** Shares reverse YTD gains and have dropped by 8.81% since January
($1 = 0.8471 euros)
(Reporting by Dimitri Rhodes in Gdask)
((dimitri.rhodes@thomsonreuters.com))