The article says:
The USA Today article claims Biden earned “$15.6 million … from speaking fees and book deals” between 2017 and 2019.
It adds that “more than $10 million of that total income was profits from Biden’s memoir ‘Promise Me, Dad’ and $3 million in profits from Jill Biden’s book.”
Following the citations within the USA Today article led readers to no details on the S-corporation.
My comment:
As I remember, there was some controversy over Biden (who claims he wants to tax rich people more) allegedly using a tax reducing scheme a few years back.
"Book deals" for politicians are just a way to launder money. There is no way at all that even 2 million of those books were sold I'd be really surprised if even 50k were sold legitimately.