They can levy whomever bank accounts they deem connected to you to satisfy your payroll liabilities. It does seem odd that they are going after your competitor but if the competitor now has one of your former employees there may be some connection.
Generally the IRS does not do this sort of thing without having all thier "ducks in a row."
If they are able to levy those bank accounts and actually collect then they probably have legal ground. (as I am assuming your competitor will refute the claim prior to the actual garnishment)
Basically the IRS can not provide your personal or business information to anyone without your consent. Generally this is provided via a Form 2848 Power of Attorney.
Hopefully this answers your question, let me know if you have any further questions.
OK. Thank you for your help.
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