stonkbuilderCOMMUNITY xStocksProof of reserves

Hold with confidence tutorial

Check the backing yourself

Each xStock should be backed one to one: at least as many shares as there are tokens in circulation, or cash in place of shares that are lent out. The issuer publishes the numbers for every product, and anyone can read them without an account.

  • 3 min read
  • Beginner
  • Checked 29 Sep 2026
Best for
Anyone who would rather check the backing than take it on trust.
You'll need
  • A browser
  • The ticker you hold
Cost
Free
Open the proof of reserves

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Worked example

TSLAx on 28 Sep 2026

TSLAx · issuer's API · 28 Sep 2026, 12:36 UTC

Custodian
189,621Tesla shares held
On-chain
189,500.81TSLAx in circulation
The checkReal data
Shares held189,621
Tokens in circulation189,500.81
Backing100.06%
Spare shares120.19
Real data from the issuer's API at 12:36 UTC: 189,621 Tesla shares held at Alpaca against 189,500.81 TSLAx in circulation, about 120 shares more than needed.

Step by step

  1. Open proof of reserves

    Go to defi.xstocks.fi/proof-of-reserves and search for the ticker.

    Screenshot: Proof of reserves on defi.xstocks.fi

    The dashboard's own figures when this was taken. They move as tokens are issued and redeemed, so they differ slightly from the API reading in the example above.

    1. 1Search a ticker
    2. 2Tokens in circulation
    3. 3Shares held in custody
    4. 4Backing ratio

    Screenshot of defi.xstocks.fi/proof-of-reserves , taken 28 Sep 2026. The live page is the source of truth.

  2. Read the two numbers

    In Custody is what the custodians hold for that product. In Circulation is the tokens in public hands. In Custody should be at least In Circulation, a Ratio of 100% or more.

  3. Get the same figures from the API

    api.xstocks.fi/api/v2/public/proof-of-reserves/TSLAx returns the same numbers as JSON, with a timestamp and the name of the custodian holding the shares.

  4. Know what it does not prove

    It is the issuer's own report of its custody accounts. The legal protections, the custodians and the security agent are set out in the prospectus and the product's Final Terms.

Open the proof of reserves

Good to know

  • The docs describe each xStock as collateralized 1:1, asset by asset, in segregated custody accounts.[1][2]
  • Where a product's Final Terms allow it, as TSLAx's do, shares may be lent out against cash collateral of the same value; lent shares stop counting as collateral until they return.[3][4]
  • On 28 Sep 2026 each of the ten largest xStocks by value was backed at or above 100%, from 100.02% (MSTRx) to 101.31% (SPYx).[5]
  • The API also lists a larger total supply for TSLAx (548,253.87 tokens); the reserve check counts only the circulating supply.[6][7]
  • The collateral accounts sit under a three-party account control agreement with an independent security agent.[2]

Sources

  1. xStocks docs: Frequently asked questions docs.xstocks.fi/docs/frequently-asked-questions
  2. xStocks docs: Product legal overview docs.xstocks.fi/docs/product-legal-overview
  3. Backed Assets: TSLAx Final Terms of 8 May 2026 (download on the TSLAx product page) assets.backed.fi/products/tesla-xstock
  4. Backed Assets (JE) Limited: Base prospectus of 8 May 2026 (on its legal documentation page) assets.backed.fi/legal-documentation
  5. xStocks DeFi dashboard: Proof of reserves defi.xstocks.fi/proof-of-reserves
  6. xStocks API: total supply of TSLAx api.xstocks.fi/api/v2/public/assets/TSLAx/total-supply
  7. xStocks API: proof of reserves for TSLAx api.xstocks.fi/api/v2/public/proof-of-reserves/TSLAx
  8. Backed Assets: Legal documentation and restricted countries assets.backed.fi/legal-documentation

Checked on 29 Sep 2026. xStocks change; the linked pages are the source of truth.