Company: GSUI
Filing Date: 2025-12-05
Form Type: S-1
Source: 0001193125-25-309828
Chunk: 45

Company: Grayscale Sui Trust (SUI)
Filing Date: 2025-12-05
Form: S-1
Chunk 45
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 the Sui Network through its influence over core developers or otherwise, such actor or botnet could manipulate the Sui Network to adversely affect the value of the Shares or the ability of the Trust to operate.

The Sui Network is currently vulnerable to several types of attacks, including:

“33% attack” where, if a validator or group of validators were to gain control of more than 33% of the total staked SUI on the Sui Network, a malicious actor could temporarily impede or delay transaction confirmation or even cause a temporary fork in the blockchain.

“50% attack” where, if a validator or group of validators acting in concert were to gain control of more than 50% of the total
staked SUI on the Sui Network, a malicious actor would be able to gain full control of the Sui Network and the ability to
manipulate the blockchain on a forward-looking basis, including censoring transactions following the achievement of
threshold, double-spending and fraudulent block propagation, while the attacker maintains the threshold. In theory, the
minority non-attackers might reach social consensus to reject blocks proposed by the malicious majority attacker, reducing
the attacker’s ability to engage in malicious activity, but there can be no assurance this would happen or that non-attackers
would be able to coordinate effectively.

“>66% attack” where, if a validator or group of validators acting in concert were to gain control of more than 66% of the total staked SUI on the Sui Network, a malicious actor could permanently and irreversibly manipulate the Sui Network, including censorship, double-spending and fraudulent transaction propagation, both on a forward-and backward-looking basis. The attacker could unilaterally finalize their preferred chain without the votes of any other stakers, and could also reverse past finalized transactions. The Sui Network’s proof-of-stake consensus mechanism requires a 2/3 supermajority of validators who have staked SUI to vote in favor in order to finalize transactions and add transactions to the Sui Network.

For example, in August 2020, the Ethereum Classic Network was the target of two double-spend attacks by an unknown actor or actors that gained more than 50% of the processing power of the Ethereum Classic Network. The attack resulted in reorganizations of the Ethereum Classic blockchain that allowed the attacker or attackers to reverse previously recorded transactions in excess of over $5.0 million and $1.0 million.

In addition, in May 2019