Make sure you have a good reason for the check. It will only be accepted to counter vandalism or disruption to Wikimedia wikis. Valid reasons include needing a block of the underlying IP or IP range, disruptive sockpuppetry, vote-stacking, and similar disruption where the technical evidence from running a check would prevent or reduce further disruption.
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Confirmed Dmitryne, KuznecovGrigory, Ruþín16, OstapBinder, MedvedevDmitriy. He did a pretty good attempt to cover tracks. Almost had me missing it. I don't speak Russian, though I do speak CU and IP. <g> — billinghurstsDrewth 14:46, 28 February 2015 (UTC)