BitMEX and BitMart both announced shutdown plans within a week, and a separate case involving Zondacrypto in Poland has added fresh urgency to a question many users cannot avoid: are exchange-held assets actually still there?
On July 23, derivatives exchange BitMEX said it would end operations, close its platform on Sept. 23, and stop accepting new user registrations immediately. The move brings an 11-year run to an end for the venue described in the article as the inventor of the perpetual contract.
Three days later, on July 26, BitMart said it had started an orderly liquidation process. All trading will stop on Aug. 26, and the exchange expects to complete the wind-down on Jan. 31, 2027. After the announcement, BitMart’s platform token BMX posted a cumulative weekly loss of 81.5%.
The article then looks back to April 2026, when Zondacrypto’s hot wallet BTC balance fell from 55.7 BTC to 0.086 BTC, wiping out 99.7% of the balance in a short period. During that stretch, the platform continued to say it was solvent. About 30,000 users were affected. The report describes the case as Europe’s most significant exchange blowup since FTX.
BitMEX and BitMart both framed their exits as voluntary shutdowns. Zondacrypto, by contrast, showed how an exchange can still say everything is normal even as assets on the books may already be missing. That is where proof of reserves, or PoR, comes in.
What PoR is supposed to prove
PoR is not a slogan. In the article’s framing, it is a mechanism that can be checked. A complete setup has two parts: proof of total assets held in reserve wallets and proof of total liabilities owed to users. Those numbers have to line up, with assets covering liabilities at a 1:1 ratio or better.
If a platform discloses only assets and not liabilities, the article says that does not amount to a complete proof-of-reserves system.
Why Merkle tree verification matters
The standard industry method is the Merkle tree. Each user’s balance snapshot is treated as a leaf node, then hashed and combined step by step until the process produces a single Merkle root. If even one balance is altered, the root changes.
The practical value goes beyond that structure. Users can obtain their own leaf-node data and calculate upward on their own to check whether their balance was honestly included in the platform’s published liabilities. In other words, users do not need to rely only on the exchange’s word.
PoR has limits, and snapshots are only one moment in time
The article also stresses that PoR is not a cure-all. A snapshot can show that assets and liabilities matched at one specific moment, but it does not rule out the movement of funds during the gap between disclosures.
That is the weakness highlighted by the Zondacrypto case, where a hot wallet balance fell 99.7% without outside observers catching it in time. In that context, the real dividing lines are not whether an exchange has ever published a PoR report, but how often it does so, whether users can verify the claims themselves, and whether outside parties have reviewed the setup.
The report says this is why major exchanges have moved from one-off reserve disclosures to monthly routines. Binance has combined Merkle tree verification with zk-SNARKs since November 2022, using zero-knowledge proofs to show that total assets cover total liabilities and that there are no accounts with negative balances, while keeping individual account data private. It has published 38 reports so far.
OKX has taken a zk-STARK approach instead. Its monthly report series has reached the 40th edition, covering more than 22 assets and around $27.7 billion in on-chain reserves.
Kraken is cited as an example of a different route, one based on accountant-led audit-style PoR reports. The underlying methods differ, but the common thread, according to the article, is regular disclosure, verifiability and privacy protection.
After more than three years of development, the piece argues, PoR has shifted from a crisis-response tool to a basic item on users’ exchange due-diligence checklist.
Ourbit’s approach: public reserves page, open-source verification and external audits
The article uses Ourbit as an example of how newer exchanges are trying to build those checks directly into their products. On its website, Ourbit publishes a public 1:1 proof-of-reserves verification page that currently lists 26 on-chain wallet addresses across 10 networks, including Bitcoin, Ethereum and BNB Chain.
According to the figures cited, the reserves currently include 656 BTC, 5,449 ETH and more than 28 million USDT, for a total value of about $80.8 million. The page shows each wallet’s balance and block height, allowing anyone to compare the information with blockchain explorers instead of relying on a one-time snapshot released only after a dispute.
To match the self-verification logic of the Merkle tree model, Ourbit has also open-sourced a verification tool on GitHub. Users can download their own leaf-node data and calculate locally from SHA256 hash values all the way to the root node, checking whether their balance was included in the total liabilities calculation.
On third-party review, the article says Ourbit has completed deep penetration testing and audits by Web3 security firm Hacken, with audit files published on Hacken’s website. It says the exchange has completed three audits in total. Hacken, founded in 2017, is described as holding ISO 27001:2022 certification and operating the CER.live security rating platform and the HackenProof bug bounty platform. The article presents the three audit rounds as a sign of ongoing review rather than a single certification exercise.
Ourbit also works with SlowMist for on-chain threat intelligence and runs a bug bounty program of up to $20,000 on BugEx, according to the report. The exchange also uses cold-wallet storage, 2FA, anti-phishing codes and 24-hour on-chain monitoring.
A less-discussed signal: whether the platform is still investing in its market presence
The piece adds another indicator that is not discussed as often but may still be useful: whether a platform continues to invest in community and market activity. In an environment where exchanges are shutting down, a continued willingness to hold offline events and maintain community operations can be read as a sign that the business intends to keep going.
The article says Ourbit has continued to sponsor blockchain industry events, expand in emerging markets and launch new product experiences such as prediction markets and Tap Trading. Whether that expansion lasts, however, still comes back to the same foundation: reserves transparency and security.
What users should ask before choosing an exchange
New exchanges will keep appearing, and older ones will keep closing. The shutdowns at BitMEX and BitMart, announced within a single week, are the latest reminder.
The article’s conclusion is straightforward. Instead of waiting for the next shutdown wave and checking after the fact, users should make a few questions routine: does the exchange publish a proof of reserves that is open and independently checkable, is the verification method something users can test themselves rather than simply trust, and does the platform undergo third-party security audits on a continuing basis?
Spending more time observing and checking those points may make a material difference the next time exchange risk surfaces.