Investing and trading platform Robinhood (HOOD) holds over $3 billion in bitcoin (BTC) in a single wallet that attracted the holdings over several months, wallet data from Arkham Intelligence shows. This makes it the third-largest bitcoin holder behind crypto exchanges Binance and Bitfinex, which hold $6.4 billion and $4.3 billion worth of tokens on single wallets respectively.

The wallet previously gained notoriety among market watchers in the past few months as the identity of its owners sparked conversations and concerns about who the mysterious owner of such a large amount of bitcoin could be.

As of Monday, Robinhood has not publically commented on these holdings.

The transfers sparked speculations ranging from the bitcoin holdings belonging to financial behemoth BlackRock, which filed for a Bitcoin ETF earlier this year, to crypto exchange Gemini shifting its users’ holdings to a wallet.

Robinhood transferred some 118,300 bitcoin to the wallet from several other smaller wallets over a three-month period, data shows. The firm told CoinDesk that it custodies all customer assets, including bitcoin.

All of these holdings are held on the Bitcoin blockchain. The first transactions were made on March 8, after which huge amounts of bitcoin were transferred until July 14, data from BitInfoCharts show.

Meanwhile, the holdings shed light on the extent of Robinhood’s bitcoin exposure despite low crypto trading volumes on its platform.

Robinhood reported crypto trading revenue of just $31 million in the second quarter, down 18% from the $38 million in the first quarter, according to its latest earnings release. The figures were 16% of the $193 million in trading revenue across all categories, which saw a 7% sequential decline, as previously reported.

Correction (23:00 UTC 8/28/2023) A previous version of this article stated that Robinhood custodies assets with Jump Trading.