Ciao marco! Piacere di conoscerti

No, fractions of a satoshi do not exist on the Bitcoin blockchain. Bitcoin is designed with a maximum divisibility of 8 decimal places, with the satoshi (0.00000001 BTC) being the smallest unit.

Any service claiming to handle Bitcoin with 16 decimal places is not reflecting the reality of the Bitcoin blockchain. They are likely using an internal representation for calculations, but this has no on-chain validity.

If no blockchain explorer shows more than 8 decimals, it’s because units smaller than a satoshi simply do not exist on the Bitcoin network.