Coinbase Custody holds 635,000 BTC on behalf of Grayscale that refuses to share proof of reserves
Coinbase Custody Trust, the institutional investment arm of Coinbase Global, holds 635,000 BTC on behalf of Grayscale Bitcoin Trust, according to a note by Coinbase Custody CEO Aaron Schnarch. Digital investment firm Grayscale has also declined to share proof of reserves, citing security concerns.
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### Instruction: Coinbase Custody holds 635,000 BTC on behalf of Grayscale that refuses to share proof of reserves

### Response: Coinbase Custody Trust, the institutional investment arm of Coinbase Global, holds 635,000 BTC on behalf of Grayscale Bitcoin Trust, according to a note by Coinbase Custody CEO Aaron Schnarch. Digital investment firm Grayscale has also declined to share proof of reserves, citing security concerns.