This article is missing information about details of what Udal law is and how it differs from other systems of law. Please expand the article to include this information. Further details may exist on the talk page.(August 2008)
The udal tenant holds without charter by uninterrupted possession on payment to the Crown, the kirk, or a grantee from the Crown of a tribute called scat (Danish: skat, now meaning "tax"), or without such payment, the latter right being more strictly the udal right. They were convertible into feus at the option of the udallers until feu was abolished in 2004.
While in the rest of Britain ownership of land extends only to the high water mark, and the Crown is deemed to own what lies below it, in Orkney and Shetland it extends to the lowest Spring ebb.
^ One or more of the preceding sentences incorporates text from a publication now in the public domain: Chisholm, Hugh, ed. (1911). "Udal". Encyclopædia Britannica27 (11th ed.). Cambridge University Press. p. 556.