As per the Karnataka Legislature Rules, intended resignation should be "in perfect format," he told reporters after meeting the disgruntled legislators.
"Unfortunately, eight of the 13 letters that reached my office (last week) were not in the format," he said.
Kumar also insisted that he was neither responsible for the current political situation nor its outcome.
"MLAs have submitted resignation in right format now..
I will have to examine whether resignations are voluntary and genuine," he added.
Kumar said he had earlier informed the legislators that if they are so intent to resign, they should resubmit their resignations in the prescribed form.
The top court earlier asked the Speaker to decide "forthwith" on Thursday about the resignation of 10 rebel Congress-JD(S) coalition MLAs, allowing them to meet him at 6 pm.
A Bench headed by Chief Justice Ranjan Gogoi said the decision taken by the Speaker has to be intimated on Friday when the court takes up the matter again.
The resignation of 16 MLAs (13 from Congress and three from JDS) has pushed the coalition government to the brink of collapse.
Two independent MLAs have also withdrawn support to the coalition government.