Looking at the repo, it appears to be based on a model trained using K2/icefall (https://github.com/k2-fsa/icefall https://github.com/k2-fsa/icefall; K2 is next

Looking at the repo, it appears to be based on a model trained using K2/icefall (https://github.com/k2-fsa/icefall https://github.com/k2-fsa/icefall; K2 is next generation of Kaldi). It claims to be based on a LSTM Transducer model trained on the Librispeech dataset as the base, and further "trained with some extra data". No further information is provided. Librispeech is CC-BY 4.0 licensed (see http://www.openslr.org/12/ http://www.openslr.org/12/).