What Data are AI Engines Being Trained On?

The fuel for Artificial Intelligence is data.  Good fuel (data) will provide good energy (answers).  However, bad fuel (bad data), will cause issues both in the long term and short term (bad answers, misleading information, untruths, and many more undesirable outcomes). There is no known, as of this broadcast date, list of data sources that any of the AI engines are being trained on.  What does that mean to the AI “consumer”?  Maybe we need a different approach to how to train these AI engines.