The Big Ten on Monday sent a formal notice to Michigan athletics notifying it of potential disciplinary action related to Michigan football's alleged illegal sign-stealing scheme.

The notice is required by Big Ten bylaws, which states: "In the event that it becomes clear that an institution is likely to be subjected to disciplinary action, the Commissioner shall notify that institution or individual at the earliest reasonable opportunity. Under no circumstances shall the Commissioner comment publicly regarding either an investigation or disciplinary action without first providing notice to any involved institution or individual."

ESPN's Adam Rittenberg was first to report the news.

Michigan could be punished based on the Big Ten's sportsmanship policy. The investigation centers on whether Michigan was scouting future opponents in-person and using video recordings to decipher coaches' signals from the sideline. Both actions are against NCAA rules.

Connor Stalions, the alleged ring leader of the sign-stealing operation, resigned Friday after refusing to cooperate with investigators. He is a retired captain from the U.S. Marine Corps and graduate of the United States Naval Academy. He was hired as an off-field analyst for Michigan in May 2022 after volunteering for several seasons.

But Stalions' banishment does not absolve the Wolverines from punishment, and Jim Harbaugh could be suspended again this season.

The push for punishment from the conference started last week after conference calls were held with every school. Other Big Ten coaches and athletic directors have reportedly attempted to pressure first-year Big Ten commissioner Tony Petitti into taking action against the Wolverines before the NCAA takes actions.

Michigan president Santa Ono on Thursday sent a letter to the Big Ten, urging for due process and to let the investigation run its full course. He met with Petitti on Friday.

The news of the notice of potential punishment came just minutes after Michigan athletic director Warde Manuel announced he would be skipping this week's College Football Playoff rankings summit in Dallas to deal with the ongoing investigation. Manuel is on the selection committee.

NCAA joins Central Michigan in investigation of Stalions on Chippewas sideline

Central Michigan athletic director Amy Folan released a statement Monday saying the investigation into whether Stalions was on the Chippewas sideline for the season opener against Michigan State is still ongoing in tandem with the NCAA. 

“Central Michigan continues its review of the matter in cooperation with the NCAA,” Folan said in a statement obtained by college football reporter Nicole Auerbach. “As this is an ongoing NCAA enforcement matter, we are unable to provide further comment at this time.”

Once Stalions’ name became a hot-button topic in the college football world, people dug through old games to see if they could find him on the sideline. Pictures and videos emerged of a man that looked like Stalions disguised as a CMU staffer at Spartan Stadium.

Ex-college football staffer says he shared docs with Michigan showing Big Ten team had Wolverines' signs

A former employee at a Big Ten football program said Monday it was his job to steal signs and he was given details from multiple league schools to compile a spreadsheet of play-calling signals used by Michigan last year.

The employee said he recently shared the documents, which showed the Wolverines' signs and corresponding plays — as well as screenshots of text-message exchanges with staffers at other Big Ten schools — with Michigan. He spoke with The Associated Press on condition of anonymity because he feared the disclosures could impact his coaching career.

The spreadsheet was compiled with details from a handful of coaches and programs across the Big Ten, the person said. He also said he gave the details to Michigan last week because he hoped it would help Jim Harbaugh's embattled program and that he believes Harbaugh and his coaches are being unfairly blamed for the actions of a rogue staffer.

Contributing: The Associated Press