There could be an easier way to do this but this was my quick-fix for it (needs to be "cleaned up"

:
Public CtrlCode
' Fill some list box with data
Private Sub CommandButton1_Click()
ListBox1.AddItem "Test1"
ListBox1.AddItem "Test2"
ListBox1.AddItem "Test3"
ListBox1.AddItem "Test4"
ListBox1.AddItem "Test5"
End Sub
Private Sub ListBox1_KeyDown(ByVal KeyCode As MSForms.ReturnInteger, ByVal Shift As Integer)
' Key_Down event traps only the first key in the Ctrl-C sequence (e.g. Ctrl). Use CtrlCode to flag that CTRL has been pressed while determining if the second key in sequence is "c" or "C".
' 17 is the key code for CTRL
If KeyCode = 17 Then CtrlCode = "Pressed"
End Sub
Private Sub ListBox1_KeyUp(ByVal KeyCode As MSForms.ReturnInteger, ByVal Shift As Integer)
If CtrlCode = "Pressed" and KeyCode = 67 Then
Set MyData = New DataObject
MyData.SetText ListBox1.Text
' Copy data to clipboard
MyData.PutInClipboard
' Now that it is on clipboard, now able to
' paste "normally" using Ctrl-v.
End If
CtrlCode = "NotPressed"
End If