However, to report instances of copyright infringement, users must first join Udemy - an obstacle described as "sleazy" by Mr Conery. A separate support email can be used by non-members, but this method of reporting content is not publicised clearly on the site.
Computer security expert Troy Hunt also found his material posted on Udemy. A course about ethical hacking - also now removed - was being sold for $47 (£31).
The Udemy version was identical to a course Mr Hunt had posted on an alternative site - although the Udemy version had the words "Hi, I'm Troy Hunt" removed from the beginning of the course.
Also, he had found that watermarks on the slides had been blurred out.
After being contacted by the BBC, Udemy responded to complaints in a blogpost, external.
It said no money had changed hands from the sale of Mr Hunt's course "as the fraudulent instructor had created coupon codes to allow students free access to the course".
The company added: "As an open marketplace of online content, we, like other platforms, face bad actors that seek to profit by stealing intellectual property and reposting it as their own.
"This is in clear violation of our terms of use and against every principle we hold as supporting open marketplaces.
"Our escalation team will be meeting after the holiday to review all of our copyright processes, including allowing people who do not have a Udemy account to use our flagging notification system."