AXT Inc's stock surged 19.41% during the overnight session on Tuesday, marking a significant rebound for the semiconductor materials company.

The rally is attributed to a combination of oversold rebound momentum and a structural supply shortage of indium phosphide (InP) materials. China's tightening export controls on InP and upstream high-purity indium have constrained global capacity, with the rejection rate for export applications from US and Japanese companies reportedly exceeding 80%. As the leading US-listed InP substrate manufacturer, AXT Inc stands to benefit from these supply chain scarcity premiums.

This overnight gain follows a period of volatility where the stock experienced significant profit-taking after cumulative gains exceeding 25% earlier in the month. While insider selling by company executives may continue to cap some upside potential, the fundamental supply-demand dynamics in the InP market appear to be driving the current positive momentum.