If you're referring to UCEPROTECTL3, that one can and should be ignored. The list's own publisher basically says "don't use this for spam filtering" because it's so wildly inaccurate (their L1 and L2 lists are the "normal" blocklists most think of). They almost never remove entries from L3 and also do not accept delisting requests for L3, so it is basically useless. The list seems to include most data center IP ranges that aren't one of the giant tech companies.
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