On another discussion their response to a similar question was something like this:

I can share that our platform is built on top of ARIMA models, but with a lot of pre-processing work done previously to try and figure out automatically the best parameters to use, as well as a lot of previous hand-tweaking done by ourselves in-house using different datasets (we started out tuning it for forecasting energy consumption, but figured that the resulting models were performing well enough to warrant testing in other domains).