U.K.-based Cenkos Securities PLC's founder and former CEO Andrew Stewart purchased shares in the company and now owns a 7.43% stake, according to a Dec. 23 filing.

The disclosure of Stewart's return to the shareholder register caused Cenkos' share price to climb 12% to 49.9 pence per share, the Financial Times reported Dec. 23.

Stewart owned about 23% of Cenkos' issued share capital in 2010 and sold almost the entirety of it in a series of share sales since then, the report said.

Cenkos CEO and co-founder Jim Durkin told the FT that Stewart returned to the company's shareholder register of his own volition.