Live feed16:33:57·1445dINSIDERFilingvia QuantisnowSEC Form 4: Williamson Ken covered exercise/tax liability with 6,631 shares, decreasing direct ownership by 3% to 184,258 units (withholding obligation)ByQuantisnow·Wall Street's wire, on your screen.IO· Ion Geophysical CorporationEnergyOriginal source