Openai - GPT2 2019 - https://openai.com/research/gpt-2-1-5b-release https://openai.com/research/gpt-2-1-5b-release Google - T5 - Feb 2020 - https://blog.resear

Openai - GPT2 2019 - https://openai.com/research/gpt-2-1-5b-release https://openai.com/research/gpt-2-1-5b-release Google - T5 - Feb 2020 - https://blog.research.google/2020/02/exploring-transfer-learning-with-t5.html?m=1 https://blog.research.google/2020/02/exploring-transfer-lear... Both of these were and still are used heavily for on-going research and T5 has been found to be decently useful when fine-tuned. Weights were available for both.