Wikipedia Verifiability Policy
Wikipedia's verifiability policy holds that claims must be attributable to reliable published sources, not based on editors' personal knowledge. It is one of three core content policies alongside no-original-research and neutral point of view.
Wikipedia's verifiability policy is one of three core content policies, alongside no-original-research and neutral-point-of-view. It holds that material on Wikipedia must be attributable to a reliable, published source — not based on an editor's personal knowledge, expertise, or unpublished analysis. A claim is considered verifiable if a reliable source supporting it could be cited, even if no citation is currently present; the citation needed tag exists to mark precisely such gaps. The policy distinguishes between truth and verifiability: an editor's belief that a claim is true is not sufficient grounds to include it. The standard is whether other readers can, in principle, check the claim against a published source. This is a deliberate design choice that trades off some epistemic ambition (Wikipedia does not adjudicate truth itself) for tractability (anyone can audit a sourced claim). It is also what makes Wikipedia legible to outsiders: every assertion is, in theory, traceable to something a reader can inspect.