Unique rules when forming that grammar are highlighted like this.
Example sentences follow these rules too!
Joining and Nesting Markers:
Verb[た/る] - means that dictionary form and ta form are accepted.
Verb[causative[て]] - means て form of the causative form of the verb.
(A) とはとは言うものの (B) is an expression used when the speaker/writer acknowledges (A) as a fact, or that (A) is widely considered to be a fact. However, despite one’s expectations, (B) is the case. It is also used when (A), while true, is insufficient, and additional details from (B) are needed to paint the whole picture. Unlike ものの by itself, this expression can be used at the beginning of a sentence.