Sub SplitDocumentTest()
Dim oRng As Range
Dim oDoc As Document

  Set oRng = ActiveDocument.Range
  With oRng
    .Collapse wdCollapseStart
    .EndOf Unit:=wdSection, Extend:=wdExtend
    .MoveEnd wdCharacter, -1
    Set oDoc = Documents.Add()
    .Copy
    oDoc.Content.Paste
    oDoc.SaveAs2 FileName:="Specification_1", FileFormat:=wdFormatXMLDocument
    Set oDoc = Nothing
    .Collapse wdCollapseEnd
    .MoveStart wdCharacter, 1
    .EndOf Unit:=wdSection, Extend:=wdExtend
    .MoveEnd wdCharacter, -1
    Set oDoc = Documents.Add()
    .Copy
    oDoc.Content.Paste
    oDoc.SaveAs2 FileName:="Specification_2", FileFormat:=wdFormatXMLDocument
    Set oDoc = Nothing
    .Collapse wdCollapseEnd
    .MoveStart wdCharacter, 1
    .EndOf Unit:=wdSection, Extend:=wdExtend
    .MoveEnd wdCharacter, -1
    Set oDoc = Documents.Add()
    .Copy
    oDoc.Content.Paste
    oDoc.SaveAs2 FileName:="Specification_3", FileFormat:=wdFormatXMLDocument
    Set oDoc = Nothing
  End With
lbl_Exit:
  Exit Sub
End Sub