United Arab Emirates-based media investment company Istithmar PJSC, through $2 billion in participation notes issued by UBS AG, now controls 2.39 percent of Time Warner Inc.'s (NYSE:TWX - news) stock and has hired one of Carl Icahn's entities as its advisor, according to a regulatory filing on Thursday.

The notes give Istithmar effective control over and economic exposure to over 109 million Time Warner shares, the filing with the U.S. Securities and Exchange Commission said.

Under the agreement, UBS does not have economic exposure or control over the shares.