The thing about Bitcoin is that it can provide any individual with a great deal of anonymity if they want it. Satoshi did that which means we don't know which coins are Satoshi's to talk about how much they are, how much they're worth and whether he has ever sold them or not.

The only thing we know for sure is that Satoshi owns only 2 keys:

• First one is the key to the output of the Genesis block. Those coins have never been moved and you can already see the balance of the address because some people sent coins to it (remember to deduct 50 if you are checking it on a broken block explorer that includes the unspendable Genesis block output)
• Second one is the key to the input Satoshi announced to own when he sent 10BTC from it to Hal Finney back in 2009 as the first bitcoin transaction ever. People have sent coins to that key as well (to the P2PKH version of it) and it hasn't moved either.