One of a number of inheritance links between constructions posited in construction grammar (2). Involves a type of inheritance (2) in which one construction is a proper sub-part of another construction but exists independently. Consider the following example.

1. The French flew Jack to the conference
2. Jack flew Example (1) is an instance of the caused motion construction.

Example (2) is an instance of the intransitive motion construction. While (1) lexcially profiles the argument roles cause (The French), theme (Jack) and goal (the conference), (2) profiles only the theme (Jack). In this sense, the construction illustrated in (2) is a proper sub-part of the construction in (1). Thus the relationship between the two constructions is captured by a sub-part link.