Sidelined AIADMK leader TTV Dhinakaran, who lost the battle for the party's 'two leaves' symbol when the Election Commission awarded it to the camp led by Chief Minister K Palaniswami and his deputy O Panneerselvam, also filed his papers.
AIADMK presidium chairman and party's nominee E Madhusudhanan and DMK's M Maruthuganesh filed their nominations with election officials here for the by-poll, necessitated by the death of Jayalalithaa, who was the sitting MLA, in December last year.
Mr Madhusudhanan was accompanied by senior party leaders, including Fisheries Minister D Jayakumar.
Mr Dhinakaran went to file his nomination with party supporters who were carrying flags with black, white and red stripes, which closely resembled the AIADMK flag.
Besides the three colours, the official AIADMK flag also has the picture of Dravidian veteran and late chief minister C N Annadurai.
Mr Dhinakaran, the nephew of jailed "deposed" AIADMK general secretary V K Sasikala, filed nomination as an independent candidate.
Incidentally, all these three candidates were in the fray for the April 12 bypoll to the city constituency which was rescinded by the Election Commission following complaints of money distribution.
Mr Dhinakaran was the candidate of the ruling dispensation backed by Palaniswami then, but this time, he would be a virtual outsider as he was sidelined and also lost the symbol case.
Mr Madhusudhanan was fielded by the then rebel camp headed by Mr Panneerselvam.
The two factions led by Mr Palaniswami and Mr Panneerselvam merged in August after the former dumped the Sasikala family.
Maruthuganesh was the DMK's choice then as well.
So far, 17 nominations have been filed for the bypoll, which is being seen as a litmus test for the ruling AIADMK, which witnessed rare rebellion and factionalism this year.
Mr Madhusudhanan and Mr Dhinakaran visited the memorial of Jayalalithaa and paid floral tributes.
Mr Madhusudhanan, accompanied by Mr Palaniswami and Mr Panneerselvam, also visited the memorials of party founder M G Ramachandran and Annadurai here after filing his nomination.
Mr Dhinakaran visited Jayalalithaa's memorial before filing his nomination.
The by-poll is also being seen as a virtual report card of the 18-month-old AIADMK government which saw three chief ministers head the state during this period.
While Mr Panneerselvam was made chief minister after Jayalalithaa's death, Palaniswami took over from him after the former rebelled against then party chief Sasikala, alleging that he was forced to make way for her elevation to the state's top post in February.