The vitamin C in Somme Serum is a particularly stable form called ascorbyl methylsilanol. Many vitamin Cs aren't stable at all and virtually evaporate on opening the bottle. Ascorbyl methylsilanol, on the other hand, is stable enough to be time released.
Somme uses something called molecular dispersion technology that is supposed to convert the vitamin C (or any other vitamin or anti-oxidant) into a molecule that can be targeted at the specific cells that need it. Although Somme claims to have independent reviews from various universities, I still don't know whether I buy this targeted molecular stuff. However, since I reckon most of my cells could use some help, perhaps it doesn't really matter.
The point is that the person who recommended Somme said she used to have severe hyperpigmentation on the right side of her face. Covered by only a tinted sunblock, there was nothing that I could see. She's been using it for 18 months. Inspiring enough for me to buy a bottle and start trying it out on my merging freckles. I'll report back.