Can anyone confirm that this is a transaction from Coinbase to an external wallet, or is it an internal transaction? It wouldn't be the first time that panic was created around such transactions, only to find out later that the funds still remained with the same company, just at a different coin address.
In addition, Coinbase has announced that it keeps about 2 million BTC in its possession, so if it is correct or approximately correct, I ask the question, what does 5% mean in the bigger picture? Spreading panic should not be something serious members of this forum deal with - and this topic is nothing but exactly that.
Partly confirmed since the balance on Coinbase wallet decreases as per the graph shown on the article. The balance will be just the same if the withdrawal is just an internal transfer besides many says that this is just a show off from Coinbase to give confidence to there user that they can still handle huge amount withdrawal without a problem since they lately boast that they are holding huge amount of Bitcoin according to there CEO tweet.
Those Bitcoin is being tracked already and lets see if this will just came back unspent to confirm the theory. I doubt too that this wallet belongs to a whale, Its either its coinbase own balance or other exchange balance that pull out in there.