FRANKFURT (Reuters) - Lanxess (>> Lanxess AG) disclosed on Monday that Berkshire Hathaway (>> Berkshire Hathaway Inc.), the conglomerate run by billionaire Warren Buffett, had acquired a 3 percent stake in the German chemicals maker.

Lanxess shares jumped 2.9 percent to 65.06 euros by 0936 GMT after the news, even though the stock was trading without the rights to a 0.70 euro-per-share dividend for the first time.

In a regulatory filing, Lanxess said that Berkshire Hathaway's General Reinsurance subsidiary took a stake that reached just over 3 percent on May 19.

The shares held by General Re - whose total financial investments excluding cash holdings stood at about $22 billion (17.13 billion pounds) at the end of last year - were worth about 180 million euros ($200 million) at that time.

General Re's stake in Lanxess crossed the 3 percent threshold after Lanxess on May 11 beat consensus estimates for first-quarter earnings on strong sales of engineering plastics and synthetic rubber, but the company warned at the time that demand would soften later this year. Shares in Lanxess, a former unit of Bayer (>> Bayer AG) whose products include pesticide ingredients, construction pigments and leather chemicals, earlier this month reached four-year highs.

Lanxess has said that after recent acquisitions worth a combined 2.6 billion euros more strategic steps could be in the offing in the second half of the year.

(Reporting by Ludwig Burger; Editing by Maria Sheahan)

By Ludwig Burger

Stocks treated in this article : Berkshire Hathaway Inc., Bayer AG, Lanxess AG