Cardano audit confirms 99.7% of voucher ADA redeemed, dismisses misconduct allegations

Input Output Global (IOG) has published the results of a months-long investigative report and forensic audit into Cardano’s ADA Voucher Program. The review, released on Sept. 3, found no evidence of wrongdoing and confirmed that nearly all vouchers had been successfully redeemed.

Conducted by law firm McDermott, Will & Schulte and accounting firm BDO, the 128-page investigation examined voucher sales, redemption processes, blockchain upgrades, and the use of unredeemed ADA.

Voucher sales were the original method of distributing ADA, Cardano’s native crypto asset, through pre-launch offerings that funded the network’s early development. Buyers received vouchers, sold in tranches under strict KYC and audited for transparency, which could later be redeemed for ADA once the network was launched.

The audit was launched after allegations surfaced in May 2025 that Cardano founder Charles Hoskinson and IOG had manipulated the blockchain during the 2021 Allegra hard fork to seize roughly $600 million in ADA, which founder Charles Hoskinson dismissed.

NFT artist Masato Alexander claimed Hoskinson used a “genesis key” to divert 318 million ADA from the reserve into other pools.

Allegations dismissed

The review concluded that all accusations against the voucher program were without basis. Investigators determined that the voucher program was structured with safeguards to prevent deceptive sales tactics.

Contrary to allegations of targeting elderly investors, the investigation found that only about 6% of vouchers were sold to individuals aged 65 and over, with just 14 vouchers from this age group remaining unredeemed.

The investigation also addressed allegations that Cardano upgrades deleted voucher holders’ “private keys.” As noted, voucher certificates contained redemption codes, not cryptographic keys, and those codes remained valid throughout the redemption process.

According to the report, the misunderstanding originated from inaccurate translations of Japanese-language terms such as “password,” which were incorrectly referred to as “private keys” in online claims.

Redemption efforts

Data from the investigation showed that 14,282 vouchers, representing 25.9 billion ADA tokens, were successfully redeemed through on-chain redemptions and the Post-Sweep Redemption Project.

By the end of Cardano’s Byron era, more than 97% of the vouchers had already been redeemed on-chain.

As of Aug. 15, 2025, 99.2% of all vouchers had been redeemed, representing 99.7% of ADA sold in the program, according to the findings.

The remaining unclaimed ADA was legally transferred to Cardano Development Holdings (CDH), a Cayman foundation, in 2023 and allocated to ecosystem development, continuity contracts, and community initiatives through Intersect, Cardano’s governance body.

“Overall, the Investigation demonstrated that Input Output and Sawyers acted diligently and created structured safeguards to ensure manual redemptions and responsible governance of funds,” the report concluded.