Just a curious question, does he/she actually use this site or any of the sub topic sites?
If so, where is his/her account?
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Joel Spolsky who is the founder and current owner of Stack Overflow and Stack Exchange has active accounts on many Stack Exchange sites, for example his Stack Overflow profile, with 183 answers and 12 questions.
His most recent call for help (i.e. asking a question) was Using Serial Plotter with Visual Studio Code, on the Arduino site.
The two co-founders, Jeff Atwood and Joel Spolsky, both have accounts here.
Adding to Shadow Wizard's answer, Jeff Atwood, the other co-founder, also has an account with high records. However, he has left the company long ago and is no longer active, nor does he own the company anymore.