First Order Projection Condition

First Order Projection Condition is a condition proposed in Selkirk (1982) which says that

All non-SUBJ arguments of a lexical category Xi must be satisfied within the first order projection of Xi (where the first order projection of a category Xi is the category that immediately dominates it, whether in word structure or in syntactic structure).

The FOPC is Selkirk's (1982) counterpart of Roeper &amp; Siegel's (1978) First Sister Principle (FSP). The FOPC as well as the FSP are intended to account for (i) the relationship between he drives a truck, truck driver, and driver of trucks, (ii) the difference in well-formedness between the compounds truck driver, on the one hand, and *quick driver (next to drive a truck quickly), and *child driver (next to a child drives a truck) on the other. The FOPC and the FSP are not equivalent. The difference has to do with the data in (i)-(iii):

(i)	 eater of pasta in trees (ii)	* tree eater of pasta (iii)	* pasta eater in trees

The FOPC accounts for the ungrammaticality of both (ii) and (iii), since one of the non-SUBJ arguments of eat is not realized within its first order projection (= tree eater in (ii) and pasta eater in (iii)). The FSP has no explanation for the ungrammaticality of (iii).

Link
Utrecht Lexicon of Linguistics