Syensqo and Solvay’s $1.7 Billion Surge Makes Case for Spinoffs

A €1.6 billion ($1.7 billion) increase in the combined market value of Solvay SA and its Syensqo SA business has strengthened the appeal of spinoffs, as conglomerates weigh strategic options in lieu of tapping the near-dormant initial public offerings market.

On Tuesday, shares of Syensqo, the chemicals maker spun offfrom Solvay, closed 27% above their reference price on their second day of trading, while the parent jumped as much as 18% over the two days. Their collective market value had swelled by 13% at the close, Bloomberg calculations show.

The gains bolster the case that conglomerates frequently use to ...