I received an email that didn't have a DKIM signature in the headers but the X-SmarterMail-Spam header had the result DKIM_Pass. I've looked through another day's email and found one from @email.barclaycard.co.uk with a DKIM signature but the X-SmarterMail-Spam header had the result DKIM_None when surely that should have been a pass or a fail. I'm on version 16.3.6705 and I've looked through the release notes for the versions beyond that and I can't see any fix that relates to this.
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
 d=email.barclaycard.co.uk; s=20141127121537; t=1531506877;
 x=1547404477; bh=6Mtj1W0qz1+q2dPiT0pUIZlPTg+w5Nbn4psSlQStykY=;
 h=From:Reply-To;
 b=OqMWXJUPF6Ly0yTjF6dvcG2coMYU6I9cjvrAbSnnieZC1ObFKfdTVzB8UI+vnz0UM
  M5M99IF61axLSShciWOXEP/p+Na0Jduj+J6s0TQpbWb3KM3rmzcxPyFGkzVLVYdjDy
  m2cBWzDB/rax0DB7ELZzBviJRNnansC1tzjw9fuf7dtiIJpmEmS3F63Pd+eHyTtbee
  RHhOAlFcE7ABuFUCMhaf0unt2SFbpBIbqNK0W6md2zfdoq30wRJYxfvnVLeDEfYWhW
  30yLdc7tAr2JN9BX6IL367ikHgi/aJAE6izJbKC4reLELlc/RjkLB03IBYekr/7+vM
  ZZBAYmfTf4nEQ==
DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws;
  s=200505; d=email.barclaycard.co.uk;
  b=H7YHfl8JVUtDfYgILv0dkZIbfvI2OFNL+Se1/o9LcyUXMGmjlLDhB3UZ3LGRHYEMl+paCQZhZbIBYvocV7iBShWF1aul1DtmEiq93RyMkO8JN3uVhgkO/2Gc+aFCgnGedZ7dG4aF0s2qNArUbAUxvHW+C3AEGJ9Sq3wT+Qsnlz0=;
 h=Date:Message-ID:List-Unsubscribe:From:To:Subject:MIME-Version:Reply-To:X-Mailer:X-mid:X-aid:Content-Type;
Date: Fri, 13 Jul 2018 18:34:37 -0000
From: "Barclaycard" <barclaycard@email.barclaycard.co.uk>