KeyBanc analyst Justin Patterson cut the stock to sector weight from overweight.
"Tenets of our thesis on ecosystem importance and monetization are playing out, with [the] shares increasing about 40% in one month (vs. Nasdaq about 11%). International is the next leg of the story, and we believe success takes time," Patterson said.
Roku shares at last check were off 2.8% to $226.44. The stock has almost quadrupled off its 52-week low above $52, set in March.
KeyBanc estimates that the San Jose, Calif., company is tracking closer to revenue growth of 55% this year than to the investment firm's estimate, and Wall Street's consensus, of 50% growth this year.
Roku has the potential for further acceleration into the fourth quarter due to the launch of the Peacock (CMCSA) - Get Comcast Corporation Class A Report streaming network and ad strength, the analyst said.
"Our view is international is the next catalyst for narrative change. However, Roku is still in the early stages of expansion, and coming from behind in markets where Android (Europe) and TV original equipment manufacturers (Asia) have large installed bases. Barring signs of more meaningful progress internationally, we struggle to see the multiple expanding further," Patterson said.
"The media landscape favors Netflix. Disney's (DIS) - Get Walt Disney Company Report recent reorganization speaks to the challenges media companies face in the current landscape, and that Netflix's combination of content and distribution matters," Patterson said.