Wikipedia:SPA

The general test for an SPA is:

Evidence that the user seems to be editing appropriately and collaboratively to add knowledge in a niche area may suggest the user is likely to be an editor with a preferred focus. By contrast, evidence that a user is also editing to add promotional, advocative, or non-neutral approaches, or has a personal or emotional interest in the area of focus, possibly with limited interest in pure editing for its own sake, is more likely to suggest the user has the kinds of concerns described in the introduction.

The following is a list of common misuses of the single-purpose account tag. You should under no circumstance consider anything that falls into the below categories as evidence for warranting an SPA tag.

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