Chinese LED manufacturer ETI announced Monday, eight company executives will be increasing shareholdings in their company to boost investors’ confidence.

Sapphire substrate concept stocks have soared lately on China’s A-Shares market, but major international sapphire substrate suppliers stock prices have plunged, according to a China Securities Journal article. Out of the major sapphire substrate manufacturers, U.S. company GT Advanced Technology (GTAT) stock prices were down 10 percent over the last three days, another U.S. company Rubicon also fell 7 percent during the same period, while Korean Sapphire Technology Company has dropped 8 percent over the last five days.