"HBO is a very, very unique asset," Stephenson said at the Goldman Sachs Communacopia Conference. "I think of Netflix kind of as the Walmart of [subscription video on-demand services]. HBO is kind of the Tiffany."
The telecom giant has been touting its new media assets and digital content portfolio since closing its acquisition of Time Warner earlier this summer. The sale gave AT&T ownership of premium channels including CNN and HBO, bolstering efforts to compete in the media and advertising space against giants such as Netflix.
AT&T executives have privately said HBO will need to get bigger and broader in order to build subscriber base.
"We think we have as good a portfolio of premium content as anybody in the industry," Stephenson said Tuesday. "In terms of long form, Warner Brothers has an [intellectual property] library that is like few others that we can conceive of, candidly."