Bill Martin, of Indie Research, said his price target on Audible is roughly $12. Martin had been skeptical on Audible ahead of Tuesday's report. His concerns were simply that Audible's stock was priced to perfection. Audible traded at 11 times this year's sales estimates and 68 times this year's earnings estimates. Martin also points out that Audible's marketing expenses for the fourth quarter was 17.9 percent of revenue, compared with 12.6 percent in the third quarter. This is a 56 percent sequential rise. Part of rise was due to the holiday-marketing push that all companies engage in. But Martin believes that it's a "clear sign that Audible could be starting to see higher churn, market saturation and new signs of competition, rather than that the company is simply 'investing in future growth.'"