Given that Scotland is not a sovereign state, it has no effective maritime boundaries; and any claims Scotland may assert are subsumed as part of claims made by the United Kingdom. It could be argued that there is no definitive 'Scottish' sector of the North Sea in the same way there isn't a Norwegian sector or a Danish sector, or indeed a UK sector. However due to the existence of two separate legal systems in Great Britain — that of Scots law pertaining to Scotland and English law pertaining to England and Wales, constitutional law in the United Kingdom has provided for the division of the UK sector of the North Sea into specific Scottish and English components.[5] The Continental Shelf Act 1964 and the Continental Shelf (Jurisdiction) Order 1968 defines the UK North Sea maritime area to the north of latitude 55 degrees north as being under the jurisdiction of Scots law[6] meaning that 90% of the UK's oil resources were under Scottish jurisdiction.[7][8] In addition, section 126 of the Scotland Act 1998 defines Scottish waters as the internal waters and territorial sea of the United Kingdom as are adjacent to Scotland.[9] This has been subsequently amended by the Scottish Adjacent Waters Boundary Order 1999 which redefined the extent of Scottish waters and Scottish fishery limits.[10][11]