HONG KONG — The Chinese internet boom has been good to Sina. Maybe, protests one of its American investors, it could have been better.

The New York-traded shares of Sina, whose Weibo service is one of China’s most popular social media platforms, have been on a tear. They have been lifted by the same surge that has put Chinese companies like the Alibaba Group and Tencent Holdings among the ranks of Amazon and Facebook in terms of stock market value.

Still, Sina finds itself embroiled in an unusual situation for a company with a surging stock price: a proxy fight. Aristeia Capital, a hedge fund based in Connecticut, is lobbying Sina shareholders to back its two candidates for the company’s board in a bid to shake up Sina’s business and give shareholders fatter returns. This week, the other shareholders will weigh in, casting their votes before a shareholder meeting set for Friday.

Proxy fights in general are not uncommon, but one between a Chinese company and an American investor is the first of its kind, according to disclosures tracked by the data provider FactSet. And the campaign has helped to underscore the limits of foreign ownership of Chinese internet companies.