Dale Tallon the GM of Chicago made a pretty big mistake when it came to retaining the rights of 4 players. Apparently the qualifying offer he mailed to Former Tiger star Cam Barker didn't reach him in time for the July 1st deadline.
Normally qualifying offers are to be delivered via fax or courier, but instead it was mailed to Barker. Because of the long weekend the mail was delayed by a day and Barker didn't get the offer until after the deadline.
What this means is that Barker was eligible to become an unrestricted free agent, rather than a restricted free agent. If you dont know what the difference between the 2 is click http://en.wikipedia.org/wiki/Free_agent and scroll down for info.
Now barker could very well have held out. NHL sources said he could probably fetch as high as 5 million a season on the open market. However Barker did an admirable thing signing in chicago for 9.25 mil over 3 years. Roughly 3 mil a season.
Former Dub player Kris Versteeg could possibly be a UFA because of this, and because of limited cap space they possibly wont be able to afford him anymore unless moves are made.
Edit: Versteeg was signed to a similar contract that barker signed
The NHLPA has filed a grievance regarding both players.