6666.T stock up 18.25% pre-market 06 Mar 2026: watch JPY 648.00 momentum

Pre-market on 06 Mar 2026 River Eletec Corporation (6666.T stock) jumped 18.25% to JPY 648.00, making it one of the top gainers on JPX. The move came on volume 401,600, above the 50-day average, and pushed price to the session high of JPY 648.00 from an open of JPY 578.00. Investors are reacting to position rotation into small-cap components of the Technology sector while the company heads toward an earnings announcement in May. We examine what drove the spike, the balance sheet, technical signals, Meyka AI grading and short-term price scenarios.