It sounds as though Jim Harbaugh's Michigan football camp this summer is not going to be popular with Big Ten coaches.

Six coaches informed The Detroit News, through athletic department communications representatives, they would not attend the June 14-17 camp in Ann Arbor: Maryland's Randy Edsall, Illinois' Tim Beckman, Iowa's Kirk Ferentz, Rutgers' Kyle Flood, Purdue's Darrell Hazell and Indiana's Kevin Wilson.

Four others indicated they were undecided: Wisconsin's Paul Chryst, Northwestern's Pat Fitzgerald, Nebraska's Mike Riley and Minnesota's Jerry Kill. Ohio State's representative called Urban Meyer's attendance "doubtful."

Two athletic department communications representatives — at Michigan State and Penn State — refused to pursue the issue with their coaches, Mark Dantonio and James Franklin, respectively.

On April 24, Harbaugh invited coaches from every college in the country to his camp, which is called "Exposure U." He presented the invitation as a "collegial gesture to provide maximum exposure (to players) for our great game of football."

The invitation was viewed by some as Harbaugh's response to criticism he received for his aggressive June "Summer Swarm" satellite camp tour. On that tour, Harbaugh and his assistants will coach nine camps in seven states over nine days.

Alabama's Nick Saban and Clemson's Dabo Swinney denounced satellite camps, with Saban calling them "ridiculous" and Swinney labeling them "combines." Coaches from the Southeastern and Atlantic Coast conferences are prohibited from participating in satellite camps; Big Ten coaches are not.

So, who will be at Harbaugh's camp?

A few hours after Harbaugh announced the camp, Michigan football recruiting operations coordinator Chris Partridge wrote on Twitter that 50 coaches had replied that they will attend the camp.

Michigan associate athletic director David Ablauf said in an email to The Detroit News the commitments were "fluid" and a list of attendees would not be provided.