[wodenokoto]

I believe Karpathy Char-RNN is from 2015 (that is at least the year on the 100-line gist and the "unreasonable effectiveness of ..." blog post[0]) but char-level RNN language models dates back to at least 2011 with [1]

So I don't think we should call him the inventor, though he definitely popularised it with his great writing and examples.

[0] http://karpathy.github.io/2015/05/21/rnn-effectiveness/ [1] Sutskever, Ilya, James Martens, and Geoffrey E. Hinton. "Generating text with recurrent neural networks." Proceedings of the 28th International Conference on Machine Learning (ICML-11). 2011.