In the Tang dynasty, Fazang (法蔵 643-712) developed his teaching on Huayan based on the teachings centered on the Avatamsakasutra (華厳経) he received from his master Zhiyan (智儼 602-668). His system of thought is organized by a classification of doctrines called the Five Doctrines and Ten Schools (五教十宗判), which was first mentioned in the Huayan yicheng jiaofen ji (華厳一乗教分記 aka 五教章).
In the Five Doctrines, the distinction of the standpoints between beings and emptiness is used to characterize Mahayana Buddhism into early (始教) and final teachings (終教). However, in his later work Huayan jing tanxuan ji (華厳経探玄記), early and final stages are distinguished by whether all beings possess the Buddha nature (and will achieve Buddhahood) or not. This shows that the criteria for distinguishing between the early and final teachings changed.
There are also some commentaries by Fazang on the texts of Tathagatagarbha thought. These commentaries contain another classification of doctrine (the Four Schools 四宗判) and also display an interest in the attainment of Buddhahood by all beings. This suggests a possible cause of the changes found in the Huayan jing tanxuan ji and provides evidence of the influence of Tathagatagarbha thought in Fazang's Huayan Doctrine.