Does the Coinbase chunk (which is like 50% on the chart) also include Grayscale custody? You probably can't track GBTC purchases this way and it is better to rely on their regulatory fillings. For other exchanges, this looks very nice and useful, I'm surprised that some well known exchanges are so low in the list and have relatively little BTC.
Institution in a manner of speaking here (BTC holder since 2010).
Mainly we buy USDT/USDC and utilise across Binance/ Kraken/Huobi etc.
Likewise when liquidating our position we do this via USDT/USDC.
Due to the amount of paperwork involved going direct through cicle/coinbase or Tether reduces our audit trail costs.
The process of entering the market is slow based on the market collapse (entering with 10-15%) of realise profits, towards the bottom and selling at stages on the way up, the % profit is then divided and a large % (85%) exits into fiat, the remaining is set for the next cycle.