Mudambi (2008) notes that “value-added is becoming increasingly concentrated at the upstream and downstream ends of the value chain” and that “activities at both ends of the value chain are intensive in their application of knowledge and creativity”. Value-added along the value chain is, thus, represented by a “smiling curve”.
Mudambi, R. (2008). Location, Control and Innovation in Knowledge-intensive Industries. Journal of Economic Geography, 8 (5), 699-725 DOI: 10.1093/jeg/lbn024