Since the source data was deleted - according to current standards and policies - their hands are probably technically clean. But there may be another angle of attack.
In the US, you're not allowed to benefit directly from a crime you committed. For example, if you rob a bank, you can't buy your mother a car with the money and say "sorry, it's gone!" when the police come knocking.
With that line of reasoning and if there was a legal, privacy, or at least a TOS breach in collecting the data, the derivative machine learning models may be tainted also. Then again, it's likely impossible to prove exactly what data went into the model, so hard to establish which models might be tainted.
In the US, you're not allowed to benefit directly from a crime you committed. For example, if you rob a bank, you can't buy your mother a car with the money and say "sorry, it's gone!" when the police come knocking.
With that line of reasoning and if there was a legal, privacy, or at least a TOS breach in collecting the data, the derivative machine learning models may be tainted also. Then again, it's likely impossible to prove exactly what data went into the model, so hard to establish which models might be tainted.