“Final Working Definition: a bullshit job is a form of paid employment that is so completely pointless, unnecessary, or pernicious that even the employee cannot justify its existence even though, as part of the conditions of employment, the employee feels obliged to pretend that this is not the case.”

“The attentive reader may have noticed one remaining ambiguity. The definition is mainly subjective.”

Then goes on to explain that many cases are obvious: like if an office worker's spending 80% of her time making cat memes. But even in more complicated cases, you're likeliest to know best. (Not managers. The higher up you are, the more people have reasons to hide things from you.) After a couple years at the same company, normally people will learn enough of the company's secrets.