ZbMATH and conflict of interest ZbMATH sent an article for post-publication review. As of a little more than a month ago, I worked at the same department in the same university as one of the authors. We have not cooperated on a paper, but have otherwise interacted.

Should I decline to review the paper due to this conflict of interest (as I would do with a peer review for e.g. a journal article), or do zbMATH reviews have more lax standards for conflicts of interest? The reviews are post-publication, and for a review database and not a journal, and furthermore they are not anonymous, so they are quite different from journal peer reviews.

The review guidelines of zbMATH did not mention conflicts of interest.
ZbMath is like Math Reviews in concept. It publishes summaries of already published articles, to help those perusing the literature to find articles of interest. These summaries are, generally speaking, not evaluative, rather informative (in some cases the published reviews are simply quotations from the article's abstract) and they are signed. Since there is no evaluation, there is not much likelihood of conflict of interest. A reviewer could downplay an important paper by writing a short succinct review, or exaggerate the importance of a minor paper by writing a long review, and one perhaps occasionally encounters things like this, but neither really does much damage, except perhaps to deflate or inflate an ego.