Delays in approvals from authorities in countries including Mexico and Brazil had forced Clariant to push back a strategic update on its tie-up with the Saudi company, known as SABIC. With those now completed, Clariant will provide an update on future collaboration "in due course".
SABIC bought the stake in January from activist investors who had scuttled Muttenz-based Clariant's planned merger with U.S.-based Huntsman Corp. It is now the biggest Clariant shareholder, ahead of a family group from Germany that holds about 14 percent.
While the Saudi company has said it has no plans to take a majority holding, the move has prompted speculation over whether it will seek to assert more control over the Swiss maker of ingredients for soaps, fire retardant and other chemicals.
"With SABIC receiving all the regulatory approvals and the transaction set to be completed, we look forward to further developing the strategic relationship between both companies in order to generate value for all stakeholders," Clariant Chief Executive Hariolf Kottmann said in a statement.
SABIC has long been a customer of Clariant, and the two companies have a plant design joint venture called Scientific Design.
Its move to buy a big stake in the Swiss company comes as Middle Eastern energy players expand into more advanced downstream chemicals operations like the catalysts that the Swiss company produces to help speed up processes at chemicals plants.
(Reporting by John Miller; Editing by Sunil Nair and Kirsten Donovan)