“We find direct evidence of large builders switching to a cooperative posture following the ruling, giving credence to the idea that clarity around regulation is a pivotal factor to determining whether to cooperate,” the paper said. “With the ruling, we find two builders responsible for over half of the non-cooperative blocks, pointing to significant dependence on a few players to facilitate the settlement of Tornado Cash transactions. This heavy dependence on a few builders reveals a surprising level of fragility in the censorship-resistance of Ethereum.”