Since 2020, CheckSig has been the first to offer public blockchain-based Proof-of-Reserves. Emulated by a few exchanges, we are still the only custodian to do so. Our unrivaled transparency ensures that all funds are always available and safe under our effective control.
At CheckSig, we believe in a provably-honest transparent custody. At least monthly, CheckSig executes a Proof-of-Reserves transaction, i.e., provides a proof that all bitcoins in custody are available and safely under our control.
This might seem so obvious to be redundant but, as a matter of fact, most crypto companies do not prove their reserves; woefully, they might be concealing losses to be discovered later on!
The Proof-of-Reserves is provided as a transaction, publicly verifiable on the Bitcoin blockchain.
Such a transaction:
This new consolidated amount represents all bitcoins under custody at the transaction date.
Please note that spending the previous consolidated amount reveals the (pre-image of the P2WSH) locking-script that protects the bitcoins under custody, making CheckSig custody completely transparent.
Finally, the Proof-of-Reserves spends from and to the consolidation address in the same transaction to proves the control of the consolidated amount at the transaction date. While address reuse is bad for privacy, it is fine in our case because the Proof-of-Reserves must be public.
Moreover, residual security concerns (e.g., nonce exfiltration) are solved by our custody protocol. In fact, we rely on a multi-level multi-signature scheme using hardware wallets Hardware Security Modules from different vendors. To learn more about our security, read about our custody protocol.
Anyway, proving our reserves does not prove them to be enough to cover the obligations we have towards our clients. To achieve a proof-of-solvency, the proof-of-reserves should be combined with a proof-of-liabilities. Unfortunately, a reliable cryptographic proof-of-liabilities is complex, always partial, hardly verifiable by clients and auditors.
All known privacy preserving approaches do not provide easy independent verification for non-technical users (see here).
Therefore, to ensure maximum transparency and accountability, the proof-of-liabilities is better delegated to external auditors. Indeed, our (internal controllers and) external auditors independently verify that the proved reserves exceed our liabilities. This verification is part of the SOC Attestations we receive.
Furthermore, even the blockchain Proof-of-Reserves could be the result of a manipulation. As example, bitcoins could have been borrowed from a third party to temporarily cover losses. Only an off-chain external auditor can detect this kind of shenanigans.
Finally, check out below our proof-of-reserves transactions and explore them on-chain. The total Bitcoin amount in custody can be verified at the current consolidation address bc1qqst9un5sz8576fy2nnqkpm4rpfh0weveqwtt8zxgjp02g2mx5q7s2vresu.
Transaction (₿) | Deposits (₿) | Fees (₿) | Withdrawals (₿) | Asset under Custody (₿) |
---|---|---|---|---|
14 Nov 2024 | 4.78021505 | 0.00022539 | 25.00000000 | 1129.32610740 |
8 Nov 2024 | 15.38534791 | 0.00013362 | 15.00000000 | 1149.54611774 |
4 Nov 2024 | 16.77233600 | 0.00021161 | 35.00000000 | 1149.16090345 |
18 Oct 2024 | 0.65292498 | 0.00007089 | 30.00000000 | 1167.38877906 |
30 Sep 2024 | 0.20000000 | 0.00002758 | 11.00000000 | 1196.73592497 |
23 Sep 2024 | 35.84442330 | 0.00014665 | 16.00000000 | 1207.53595255 |
21 Aug 2024 | 350.44062247 | 0.00029076 | 0.00000000 | 1187.69167590 |
17 Jul 2024 | 14.65619842 | 0.00043862 | 0.00000000 | 837.25134419 |
12 Jun 2024 | 18.81667410 | 0.00126952 | 15.00000000 | 822.59558439 |
14 May 2024 | 55.16822599 | 0.00062078 | 5.00000000 | 818.78017981 |
16 Apr 2024 | 8.87802825 | 0.00096990 | 0.00000000 | 768.61257460 |
15 Mar 2024 | 0.39436028 | 0.00034814 | 20.00000000 | 759.73551625 |
5 Mar 2024 | 48.48490612 | 0.00220815 | 15.00000000 | 779.34150411 |
2 Feb 2024 | 14.54261109 | 0.00196273 | 13.95420166 | 745.85880614 |
19 Jan 2024 | 40.08728812 | 0.00309088 | 0.00000000 | 745.27235944 |
19 Jan 2024 | 1.78397518 | 0.00087578 | 0.00000000 | 705.18816220 |
22 Dec 2023 | 13.48844704 | 0.00242493 | 8.00000000 | 703.40506280 |
7 Dec 2023 | 36.04947226 | 0.00202305 | 0.00000000 | 697.91904069 |
3 Nov 2023 | 5.36556542 | 0.00008045 | 0.00000000 | 661.87159148 |
3 Oct 2023 | 18.43152443 | 0.00011139 | 0.00000000 | 656.50610651 |
4 Sep 2023 | 0.00000000 | 0.00003383 | 5.00000000 | 638.07469347 |
29 Aug 2023 | 5.01147999 | 0.00008469 | 0.00000000 | 643.07472730 |
30 Jul 2023 | 5.77611820 | 0.00016048 | 0.00000000 | 638.06333200 |
30 Jun 2023 | 33.98118495 | 0.00046136 | 0.00000000 | 632.28737428 |
2 Jun 2023 | 14.46154197 | 0.00046083 | 0.00000000 | 598.30665069 |
3 May 2023 | 13.17154810 | 0.00091026 | 0.00000000 | 583.84556955 |
30 Mar 2023 | 25.92374635 | 0.00016008 | 8.00000000 | 570.67493171 |
3 Mar 2023 | 0.01119078 | 0.00002516 | 5.00000000 | 552.75134544 |
28 Feb 2023 | 16.62947373 | 0.00086856 | 0.00000000 | 557.74017982 |
9 Feb 2023 | 11.03447299 | 0.00020804 | 0.00000000 | 541.11157465 |
20 Jan 2023 | 10.69454563 | 0.00010402 | 0.00000000 | 530.07730970 |
23 Dec 2022 | 7.66376412 | 0.00006329 | 0.00000000 | 519.38286809 |
2 Dec 2022 | 34.11648757 | 0.00029334 | 5.00000000 | 511.71916726 |
3 Nov 2022 | 12.54438499 | 0.00008004 | 5.00000000 | 482.60297303 |
4 Oct 2022 | 7.94617080 | 0.00011877 | 0.00000000 | 475.05866808 |
3 Sep 2022 | 11.43284996 | 0.00001651 | 0.00000000 | 467.11261605 |
2 Aug 2022 | 14.23876819 | 0.00005788 | 0.00000000 | 455.67978260 |
6 Jul 2022 | 32.62741757 | 0.00020804 | 0.00000000 | 441.44107229 |
6 Jun 2022 | 4.95127001 | 0.00002238 | 0.00000000 | 408.81386276 |
17 May 2022 | 13.92010123 | 0.00006018 | 0.00000000 | 403.86261513 |
3 May 2022 | 14.26250604 | 0.00006552 | 0.00000000 | 389.94257408 |
1 Apr 2022 | 28.10778268 | 0.00009213 | 0.00000000 | 375.68013356 |
4 Mar 2022 | 8.32775921 | 0.00013104 | 0.00000000 | 347.57244301 |
2 Feb 2022 | 14.29410966 | 0.00014470 | 0.00000000 | 339.24481484 |
5 Jan 2022 | 13.84709331 | 0.00006018 | 0.00000000 | 324.95084988 |
22 Dec 2021 | 21.32797471 | 0.00013071 | 10.09516878 | 311.10381675 |
29 Nov 2021 | 26.51869064 | 0.00014667 | 8.12112682 | 299.87114153 |
29 Oct 2021 | 90.43568346 | 0.00018396 | 6.65512106 | 281.47372438 |
30 Sep 2021 | 11.65154583 | 0.00016460 | 6.80705070 | 197.69334594 |
1 Sep 2021 | 13.90389341 | 0.00007370 | 0.00000000 | 192.84901541 |
2 Aug 2021 | 4.97480450 | 0.00016214 | 0.00000000 | 178.94519570 |
2 Jul 2021 | 32.06748252 | 0.00051181 | 0.00000000 | 173.97055334 |
2 Jun 2021 | 8.95164489 | 0.00027216 | 0.00000000 | 141.90358263 |
1 May 2021 | 7.24822810 | 0.00030954 | 0.00000000 | 132.95220990 |
1 Apr 2021 | 21.21598524 | 0.00057939 | 1.00000000 | 125.70429134 |
1 Mar 2021 | 22.78825901 | 0.00051181 | 0.00000000 | 105.48888549 |
2 Feb 2021 | 0.00000000 | 0.00004851 | 0.00000000 | 82.70113829 |
31 Jan 2021 | 32.07315051 | 0.00031248 | 0.00000000 | 82.70118680 |
1 Jan 2021 | 18.03542688 | 0.00051181 | 0.00000000 | 50.62834877 |
2 Dec 2020 | 12.71367043 | 0.00073700 | 0.00000000 | 32.59343370 |
3 Nov 2020 | 0.00000000 | 0.00006930 | 0.00000000 | 19.88050027 |
12 Oct 2020 | 19.88127787 | 0.00070830 | 0.00000000 | 19.88056957 |
Altcoins does not support native multi-sig: because of that, we only provides our addresses whose balances can be verified (i.e., proof-of-addresses, a.k.a. proof-of-balances). The Proof-of-Reserves is only implicit when we spend from these addresses.
0x48e3593A70b0ed9D1572A246C4d1c3fAED2415D6
0xEC738cf775822AABA713bd283D095Eb7b5100CF4
0xbc88303F12e73CBe708cE2Cf30AFf7685b1ae625
0xe421002905E8c7Cb37350b801193371B4592B6DF
© CheckSig S.r.l. Società Benefit - P.IVA 11028330964 | CheckSig Suisse AG - CHE-183.628.610