Michael Saylor, Executive Chairman of Strategy, has criticized on-chain proof-of-reserves, saying that publishing wallet addresses can create security risks.
Speaking at a side event during the Bitcoin 2025 conference in Las Vegas, Saylor called the common method “a bad idea.” He said public wallet data could make it easier for attackers to study large crypto holdings.
I asked @saylor if @MicroStrategy has any plans to publish on-chain proof of reserves
His answer will SHOCK you
“It’s a bad idea.”
– Security Risk
– Irrelevant without also having Big 4-audited liabilitiesCheck it out ???? pic.twitter.com/tIxUckgbEp
— Mitchell ✝️???????? (@MitchellHODL) May 27, 2025
Why Saylor questioned proof-of-reserves
Proof-of-reserves lets users check whether a crypto company controls enough assets to cover reported customer balances. The practice became much more common after the FTX collapse, as exchanges tried to give users more proof that their funds were backed.
Saylor’s concern is about what happens when that proof is put directly on-chain. If a company publishes wallet addresses holding billions of dollars in Bitcoin or other assets, attackers can see where valuable funds sit and watch those wallets over time.
He also said proof-of-reserves can leave out an important part of the picture: what a company owes. A firm may show that it owns billions in crypto while its debts, loans or other claims remain unclear.
That does not make proof-of-reserves useless. Binance and OKX have used reserve reports to give users more information. The issue is how much those reports reveal and what they leave out.
Also Read: Michael Saylor Says Bitcoin Advocacy Is Free Speech in the US
Proof-of-reserves has changed since Saylor’s comments
The debate has moved since May 2025. In 2026, some reserve systems use Merkle trees and other cryptographic tools to let users check that their balances are included without publishing every customer’s private account details. Proof-of-reserves can also include liability checks, which give users a better view of whether assets cover what the company owes.
The timing of the data also matters. A reserve report is a snapshot. If an exchange moves assets after the check, the report may no longer show its current position. This is why users need to look at the date, method and scope of each report.
Strategy has also changed greatly since Saylor made his comments. The company held 576,230 Bitcoin when the original report was written. Its latest company records show 847,666 Bitcoin as of September 28, 2026.
That makes the security question more important for Strategy. Its Bitcoin holdings now represent tens of billions of dollars in assets. A public list of wallet addresses could therefore reveal valuable information about where a very large amount of Bitcoin is stored.
Saylor has continued to favor company financial reports rather than publishing a full list of Strategy’s Bitcoin wallets. The debate is now less about whether crypto firms should show proof and more about how they can prove their assets without creating a new security problem. Users also need to know whether the proof covers both assets and liabilities.
Enjoyed this? Bookmark DeFi Planet, explore related topics, and follow us on Twitter, LinkedIn, Facebook, Instagram, Threads, and CoinMarketCap Community for seamless access to high-quality industry insights.
Take control of your crypto portfolio with DEFI PLANET PRO, DeFi Planet’s suite of analytics tools.
