Frank Centofante is a world class custom knifemaker and has collaborated with Spyderco on several designs. Beeing a knifemaker since 1970, he has produced a lot of knives, all of which are very high standard and sought after by collectors. His work is easily distinguishable and that goes for his collaborations with Spyderco as well. Frank Centofantes custom knives usually always contain fileworked liners, something his first collaboration with Spyderco, the C25 Frank Centofante also does.
Frank Centofante Makers mark can be found here
Some information regarding Frank Centofantes collaborations with Spyderco can be found here