  One of the defining features of a cryptocurrency is that its ledger,
containing all transactions that have evertaken place, is globally visible. As
one consequenceof this degree of transparency, a long line of recent re-search
has demonstrated that even in cryptocurrenciesthat are specifically designed to
improve anonymity it is often possible to track money as it changes hands,and
in some cases to de-anonymize users entirely. With the recent proliferation of
alternative cryptocurrencies, however, it becomes relevant to ask not only
whether ornot money can be traced as it moves within the ledgerof a single
cryptocurrency, but if it can in fact be tracedas it moves across ledgers. This
is especially pertinent given the rise in popularity of automated trading
platforms such as ShapeShift, which make it effortless to carry out such
cross-currency trades. In this paper, weuse data scraped from ShapeShift over a
thirteen-monthperiod and the data from eight different blockchains to explore
this question. Beyond developing new heuristics and creating new types of links
across cryptocurrency ledgers, we also identify various patterns of
cross-currency trades and of the general usage of these platforms, with the
ultimate goal of understanding whetherthey serve a criminal or a profit-driven
agenda.
