What did the original Tao Te Ching use for punctuation?
So far, the earliest version of Tao Te Ching found is on the Guodian Chu Bamboo Slips, written in the Warring States era State of Chu.

From 楚簡書法网 (http://www.cjsfw.net/Html/?287.html, http://www.cjsfw.net/Html/?283.html):



The text is given in verses, beginning with an 8-character rhythm, and the punctuation marks are found on the bottom right of the terminal character for the verse, as a verse breaker. The punctuation does not strictly correspond to a full stop or comma of today.