By Kosaku Narioka

Daiichi Sankyo Co. shares rose sharply Monday morning after the Japanese drugmaker said an arbitrator ruled in its favor in a dispute over a cancer drug technology.
The stock was recently 14% higher at 4,200 yen ($31.47) after rising as much as 17% earlier.

Daiichi Sankyo said Saturday that an arbitrator issued a decision in a dispute between the company and Seagen Inc., denying all claims made by the American biotechnology company over an antibody-drug conjugate technology.
Daiichi Sankyo said Seagen had claimed certain intellectual property rights related to the antibody-drug conjugate technology and filed an arbitration demand with the American Arbitration Association in November 2019.
Roger Dansey, Seagen’s interim Chief Executive Officer, said in a statement that while the arbitration decision was disappointing, it was important for the company to pursue the legal action. He added the ruling would not affect its existing business.
Jefferies analysts Naoya Miura and Stephen Barker said in a research note that they had provisionally assumed 5% of royalty payments for the possible settlement from net sales of Daiichi Sankyo’s drugs using the technology from the mid-2022.
“This conclusion not only shows that Daiichi Sankyo was not obliged to pay any royalties, but also demonstrates Daiichi’s strength of legal actions,” the analysts said.
Write to Kosaku Narioka at kosaku.narioka@wsj.com