China’s fury over Tokyo’s decision to discharge treated wastewater from the Fukushima nuclear plant is producing a rare beneficiary among Japanese stocks as tensions heighten.

Tobila Systems Inc., an Aichi-based developer of call-screening software for mobile phones, has seen its stock surge more than 10% since the water release on Aug. 24, a move that reportedly set off a torrent of angry calls from China to groups and individuals in Japan. Tobila, or “gate” in Japanese, announced Wednesday that it will offer a new feature for corporate customers that blocks overseas countries as the number of phone calls from China surges.

Fury and unease among the Chinese public have buffeted Japanese companies that are especially reliant on demand from Asia’s largest economy. Tokyo-based cosmetics firm Shiseido Co., which gets 30% of its revenue from China, has slumped 9% over the past two months amid online calls to boycott. China also suspended seafood imports from Japan, impacting shares of Nissui Corp. and sushi chain operator Genki Sushi Co.

“In terms of the overall macroeconomic impact on the market as a whole, the effect on individual consumption behavior in China will have a large impact,” said Takeru Ogihara, chief strategist at Asset Management One Co.

For Tobila Systems, the stock market is waiting to see how much rising tensions actually contribute to revenue, said Shoichi Arisawa, an analyst at Iwai Cosmo Securities Co., adding that the jump in shares will likely level out.