Yahoo co-founder Jerry Yang has left the company, the latest dramatic change at the top executive level of the embattled Internet company.

Yang, who was involved both in Yahoo's rise to Internet titan in the late 1990s and early 2000s and its fall from grace in the past six years, resigned effective Tuesday from all his posts at the company.

Specifically, he quit his positions in Yahoo's board, and in the boards of Yahoo Japan Corporation and Alibaba Group Holding, the company said in a statement.

"My time at Yahoo, from its founding to the present, has encompassed some of the most exciting and rewarding experiences of my life. However, the time has come for me to pursue other interests outside of Yahoo," Yang wrote in a letter to Board Chairman Roy Bostock.

Yang also said in the letter that he is "enthusiastic" about the recent appointment of former PayPal President Scott Thompson as Yahoo CEO and about the company's prospects for future success.

(More to come)

Juan Carlos Perez covers search, social media, online advertising, e-commerce, web application development, enterprise cloud collaboration suites and general technology breaking news for The IDG News Service. Follow Juan on Twitter at @JuanCPerezIDG.