\documentclass[12pt]{article}
\usepackage{seqsplit}
\usepackage{expl3}
\usepackage[T1]{fontenc}
\ExplSyntaxOn
\let\oldseqsplit\seqsplit% Copy \seqsplit
\renewcommand{\seqsplit}{% Redefine \seqsplit to...
\expandafter\oldseqsplit\expandafter}% ...expand its argument before processing it
\begin{document}
\gdef \ReferencedIDs{,2014.11.14,2014.11.14,2014.11.17,2014.11.14,2014.07.18.tm,2014.11.12.tm,2013.10.05.kanjur,2013.10.05.powai,2013.10.06,2013.10.28.zhm,2013.10.17,2013.10.22,2013.10.14.ks,2013.10.06,2013.10.17,2013.10.22,2013.10.24,2013.10.28,2013.10.30,2013.11.11,2014.09.05.tm,2014.0…