Some opposition members had complained about Mr Thakur using his mobile phone to shoot a video of their protests in the Well of the House on July 24.
The Speaker has herself investigated the matter but there was no evidence found against Mr Thakur for filming the proceedings of the House, said the official in the Lok Sabha secretariat.
The Speaker and other senior officials have seen the footage of the Lok Sabha TV of the given day, but there was nothing as claimed by opposition, the official said.
Yesterday, Ms Mahajan had warned Mr Thakur for allegedly filming the video inside the House, but a dissatisfied opposition demanded action against him, as had been taken earlier against AAP's Bhagwant Mann.
Mr Mann, who was suspended for two sessions for shooting a video in the Parliament complex, had also written a letter in this regard to the Speaker.
In the AAP MP's case, the evidence was available as he had posted the video on Facebook and an all-party committee was formed to investigate the matter, the official said, adding, but in Mr Thakur's case, he has tendered an apology and there is no proof against him.