We are on our second one already. You know the format, "if you have revenues over $350,000 and any nexus in MI - gotcha". They even threaten that if you don't respond they'll assess tax! In our case they got the corporate name wrong.
The nexus definition would apply to affiliates. Seems just too risky to keep up an affiliate program anymore - aren't there about ten states now that will consider an affiliate as nexus for sales tax liability?
Poor Michigan, such a financial train wreck that they have marshaled the bureaucrats and sic'ed them on the e-commerce community.
We are going to see nothing but more of these in the future as one after another state scrambles for cash.
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Michigan Business Tax [michigan.gov] Use on page search for references to Nexus
[edited by: lorax at 10:22 am (utc) on Apr 27, 2010]