Matthey's stock jumped as much as 35% to 2,536 pence on Friday, its highest since November. A London trader, on condition of anonymity, said the stake deal could be a prelude to "some kind of move", referring to possible transactions.

Standard Industries bought U.S.-based global specialty chemical company W. R. Grace & Co a year ago in a $4.63 billion deal.

As of Thursday, Matthey had a market value of 3.47 billion pounds ($4.36 billion).

Standard's stake disclosure comes a few months after Johnson Matthey announced plans to sell or exit its battery materials business in November. Its stock had slumped 32% since that announcement.

"We would consider this to be something like an ideal owner for (Johnson Matthey), operational overlap on the process catalyst business and an ability to take a long-term view on the cash generation from the Clean Air business," analysts at Jefferies wrote in a note.

Standard Latitude Master Fund, controlled by Standard Investments and the co-chiefs of Standard Industries, would now be Matthey's fifth-largest shareholder, according to Refinitiv data.

($1 = 0.7966 pounds)

(Reporting by Yadarisa Shabong in Bengaluru; additional reporting by Joice Alves in London; Editing by Krishna Chandra Eluri)