-- Collect the matches
SELECT l.ID ; 
FROM LARGE l ;
INNER JOIN small s ;
	ON s.ID <> l.ID ; 
	AND LARGE.Z5 = small.z5 and Large.ln = small.ln and Large.fn = small.fn ;
INTO TABLE SuppressedRows.DBF ; 

-- Then use the ID's to restrict table LARGE 
SELECT l.ID ; 
FROM LARGE l ;
WHERE l.ID NOT IN (SELECT ID FROM SuppressedRows) ;
INTO TABLE SuppressedRows.DBF ;

-- You might be able to do this in one step (it's a while since I've used Foxpro SQL)
SELECT l.ID ; 
FROM LARGE l ;
WHERE l.ID NOT IN ( ;
	SELECT l.ID ; 
	FROM LARGE l ;
	INNER JOIN small s ;
		ON s.ID <> l.ID ; 
		AND LARGE.Z5 = small.z5 and Large.ln = small.ln and Large.fn = small.fn) ;
INTO TABLE SuppressedRows.DBF ;