Unanswered questions about the NCAA's investigation into the alleged sign-stealing operation at Michigan

On Wednesday, the NCAA informed Michigan and the Big Ten that it was investigating whether, industry sources say, the Wolverines were using illegal in-person scouting to steal the play signals of future opponents.

The Big Ten has already informed future Michigan opponents of the investigation so they can adjust accordingly, including Michigan State, which hosts the second-ranked Wolverines on Saturday.

In terms of NCAA rules, what actually matters here?

Here are some unanswered questions, theories and speculation about the still-fluid NCAA investigation into Michigan football over scouting/sign-stealing concerns.