Ethereum’s market capitalization currently sits at $523 billion, overtaking global payment cards firm Mastercard.

An unidentified entity has been accumulating Ether aggressively over the past week — buying 221,166 ETH as the asset rallied by 21% over the same timeframe.

In the past 24 hours alone, the “mysterious institution” bought $212 million of Ether 

, according to data analytics platform Lookonchain.

The whale tracker said the entity is using six different wallets to store its Ether, which it acquired from Galaxy Digital, FalconX and BitGo. The wallet with the most Ether has $181 million worth, while the wallet with the least Ether still has $128 million worth.

The buying comes as Ether addresses with over 10,000 ETH in holdings reached 868,886 on Saturday, the highest it’s been in a year, according to Glassnode.