A transaction of 1432.92 btc happened today https://blockchair.com/bitcoin/address/1E6nViR5Xv1wyNXg87SamvtLJ5TyXuksLC .
The odd thing about this address is it ( almost ) contains block rewards from early days , specifically first reward is from block #2718 which is less than a month since launch . Only 2 transactions are not block rewards , a 0.01 btc and a 32.91 btc . All the other are coinbase rewards of 50 btc .
That's actually a huge amount of money (38.26M$ at this current rate). I would say he is probably one of the early investors in Bitcoin who has been holding onto his coins for all these years and now he's trying to transfer them to a more secure wallet, this is just my guess! The odd thing about this address is it ( almost ) contains block rewards from early days , specifically first reward is from block #2718 which is less than a month since launch . Only 2 transactions are not block rewards , a 0.01 btc and a 32.91 btc . All the other are coinbase rewards of 50 btc .
I don't think he will simply cash out all of his Bitcoin because that wouldn't be very smart. If he was able to hold onto his Bitcoin all these years and knew that the price of Bitcoin would increase in the future, why wouldn't he continue holding on for a bit longer?
Did satoshi came back to spend his coins ? A very early miner or an early OTC buyer decided to take profits ?
Everything is possible. It could be Satoshi, an early miner, or even a random person who forgot about their wallet seed phrase or private keys and has now recovered them. It is difficult to determine with certainty who the owner of that wallet is. 
Time will tell . I'll try to dig more to see if i can find anything . Any opinions or findings are appreciated .
If you find any further information about this it would be great if you could share more. 