The billionaire boosted his stake to 13.8 percent from 12.7 percent previously, according to the wire service. Icahn has upped his exposure to Cheniere eight times since he took his initial 8.2 percent position in August.
The stock was about 1.5 percent lower in extended trading, after a day in which it slid 5.3 percent amid a drop in the price of natural gas and crude oil. It has fallen more than 40 percent this year.
Icahn was already Cheniere's largest shareholder, according to FactSet.
For the third quarter, the company posted a net loss of $297.8 million, or $1.31 per share.
Cheniere did not immediately respond to CNBC's request for comment.