Cryptocurrency investment product provider Grayscale Investments has refused to provide on-chain proof of reserves or wallet addresses to show the underlying assets of its digital currency products citing “security concerns.”

In a Twitter thread addressing investor concerns, Grayscale laid out information regarding the security and storage of its crypto holdings and said all crypto underlying its investment products are stored with Coinbase’s custody service, stopping short of revealing the wallet addresses.

“We know the preceding point in particular will be a disappointment to some,” Grayscale added, “but panic sparked by others is not a good enough reason to circumvent complex security arrangements that have kept our investors’ assets safe for years.”