Shares of Clearwire Corp. (Nasdaq: CLWR) are down in trading after an SEC filing disclosed late yesterday that chairman Craig McCaw is resigning, effective immediately.

CLWR shares are down 1.51 percent as of 10:55 a.m. (EDT)

The financially beleaguered wireless networking company provided no specific reason for McCaw’s departure but said the decision “is not due to any disagreements with the Company on any matters relating to the Company’s operations, policies, or practices.”

Sprint (NYSE: S) has a majority stake in Clearwire.