Decapeptide-12 is a synthetic peptide, which acts as tyrosinase inhibitor (tyrosinase is actually a group of enzymes that contribute to the skin pigmentation process and skin melanin regulation).
Decapeptide-12 was developed at Stanford University and created as a means of promoting the expression of melanin in hopes of fighting skin hyperpigmentation and dark spots.
Though we are still missing large scale scientific studies, some preliminary data shows positive results.