A posting sits open for four months. It gets reposted the week you finally hear back, with a rejection you're pretty sure was automated. That job was probably never getting filled, not by you or anyone else who applied in month one. You spent two hours tailoring a resume for a listing that existed to satisfy an internal requirement that had nothing to do with hiring.
Ghost jobs are real, common, and not a conspiracy theory. Companies post roles to keep a pipeline warm for when budget actually opens up. Some post them to make growth look real to investors or to employees watching headcount. Some are required by policy to post externally even when they already know who's getting the job internally. None of that is about you, and none of it is something you can fix by writing a better cover letter.
What to actually check before you spend real time
How long has it been open. Most job boards show a posted date. Anything sitting past 45 days without a repost or an edit is worth suspicion. A role that's been live for four months and never closed either has a very specific bar nobody's cleared, or was never really open.
Does it get reposted on a cycle. Search the exact title and company. A listing that reappears every few weeks, often with a slightly different req number, is a strong signal it's being used to keep a pipeline stocked rather than to fill a seat now.
Is the req number consistent across boards. If you can see one on LinkedIn and a different one on the company's own careers page for what reads like the same role, that's not necessarily damning on its own, but combined with the other signals it adds up.
Does the company have a pattern of doing this. A quick search for the company name plus "ghost job" turns up more than you'd expect. Some companies are notorious for it, and if a hundred other candidates in forums are describing the same silence you're experiencing, that's data.
What to do about it
Not nothing, and not nothing at all like it doesn't exist. Apply if the role is genuinely a fit, because pipelines do eventually open and someone eventually gets hired from that stack of applications even for postings that sat for a while. Just don't spend three hours tailoring a resume for a listing with every ghost-job signal lit up. Spend fifteen minutes and move your real energy to postings that look like someone is actually reading them: recently posted, a specific hiring manager named, a reasonable and specific list of requirements instead of a wish list that reads like it was assembled by five different people who never talked to each other.
The frustrating part isn't that ghost jobs exist. It's that they're invisible from the outside until you know what to look for. Once you do, most of them stop wasting your time.