  Crowdworking platforms provide the opportunity for diverse workers to execute
tasks for different requesters. The popularity of the "gig" economy has given
rise to independent platforms that provide competing and complementary
services. Workers as well as requesters with specific tasks may need to work
for or avail from the services of multiple platforms resulting in the rise of
multi-platform crowdworking systems. Recently, there has been increasing
interest by governmental, legal and social institutions to enforce regulations,
such as minimal and maximal work hours, on crowdworking platforms. Platforms
within multi-platform crowdworking systems, therefore, need to collaborate to
enforce cross-platform regulations. While collaborating to enforce global
regulations requires the transparent sharing of information about tasks and
their participants, the privacy of all participants needs to be preserved. In
this paper, we propose an overall vision exploring the regulation, privacy, and
architecture dimensions for the future of work multi-platform crowdworking
environments. We then present SEPAR, a multi-platform crowdworking system that
enforces a large sub-space of practical global regulations on a set of
distributed independent platforms in a privacy-preserving manner. SEPAR,
enforces privacy using lightweight and anonymous tokens, while transparency is
achieved using fault-tolerant blockchains shared across multiple platforms. The
privacy guarantees of SEPAR against covert adversaries are formalized and
thoroughly demonstrated, while the experiments reveal the efficiency of SEPAR
in terms of performance and scalability.
