Overview
Accession (Latin accessio) is a method of original acquisition of property under Scots property law. It operates to allow property (the accessory) to merge with (or accede to) another object (the principal), either moveable or heritable. Accession derives from the Roman-law concept of the same name. Other jurisdictions employ similar rules. The leading case in this area is said to be Brand's Trustees v Brand's Trustees (1876) 3 R (HL) 16.
A common example is a tree (the accessory) acceding to the land (the principal), thereby the tree is owned by the owner of the land on which it is planted by the operation of accession. Accession may appear similar to other modes of original acquisition, but each mode has discrete differences. Importantly, accession does not produce a new object (nova species) in itself, such as with specificatio; accession merely attaches one object (the accessory) to another (the principal).
Types of accession
There are broadly two types of accession: (1) natural accession and (2) human accession.
Natural accession
Natural accession (accessio naturalis) occurs by the operation of nature alone. Examples: A tree sapling owned by C is planted in a garden owned by B; a cow belonging to F impregnates a cow belonging to G, thereby acceding ownership of the calf foetus to G.
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