YOFC's stock price surged 7.97% during intraday trading on Friday, marking a significant upward movement for the optical fiber and cable manufacturer.

The rally appears to be driven by two key factors. First, FTSE Russell announced that YOFC will be added to the FTSE China 50 Index, with the adjustment taking effect after the market close on June 18. This inclusion in a widely tracked benchmark is expected to trigger mandatory passive fund buying around the effective date. Additionally, the company was also added to the HKEX Tech 100 Index, effective June 15.

Second, fundamental industry conditions are supporting the stock. Domestic G.652.D single-mode fiber prices have surged approximately 400% from early last year to March, creating a historic upcycle for the fiber optic sector. Analysts note that optical preform capacity expansion lags behind fiber demand, while AI data center buildouts, overseas telecom recovery, and emerging applications create overlapping demand drivers that are expected to sustain the supply shortage.