R/mileycyrus. r/mensrights. r/daftpunk. r/floridaman. These are the subreddits where, for one reason or another, Reddit doesn’t appear to allow advertising, according to a third-party tool.

The results, pulled from the 2,500 most popular subreddits run through an API called Pushshift, show that despite spending the last decade courting advertisers and trying to address brand-safety concerns, Reddit’s actual brand-safety approach appears to be cautious, making it seem somewhat unpredictable and inconsistent.

“It feels like this has been done independent of any consultation with the advertising community…it probably tells you a bit more about the lack of sophistication, like the actual controls that they have in the community or their ad-approval process,” said Joshua Lowcock, global chief media officer at UM Worldwide.

He told Marketing Brew that advertisers can request and choose to run their ads on specific subreddits, with Reddit reserving the right to decline. The platform stopped serving programmatic ads last year, though advertisers can target audience interests and block keywords they deem unsafe thanks to its partnership with Oracle.

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