Matter Labs, the developer behind zkSync, is facing allegations from the defunct blockchain company BANKEX, which claims that two of its former employees misappropriated proprietary technology to establish zkSync. In response, Matter Labs has labeled these allegations as "baseless".

This legal dispute adds to a series of controversies surrounding Matter Labs. In 2023, the company was accused by Polygon Zero of copying performance-critical components of its Plonky2 zero-knowledge system code without proper attribution. Matter Labs CEO Alex Gluchowski denied these claims, stating that only about 5% of zkSync's Boojum code was based on Plonky2 and that proper acknowledgment was made in the README file and introduction post. However, he admitted that zkSync could have handled attribution more effectively and criticized the public allegations as contrary to the open-source ethos.

Additionally, in 2024, Matter Labs faced backlash from the cryptographic community for attempting to trademark the term "ZK" (zero-knowledge), a fundamental concept in cryptography. Prominent figures in the field, including ZK-proof co-inventors Shafi Goldwasser and Silvio Micali, StarkWare CEO Eli Ben-Sasson, and Polygon co-founders Sandeep Nailwal and Brendan Farmer, condemned the move as an "IP grab" that violated the collaborative spirit of the open-source community. In response to the criticism, Matter Labs withdrew its trademark applications and clarified that its registered trademarks were intended to prevent confusion with its products, not to claim ownership over the term "ZK".

These incidents collectively paint a picture of a company grappling with its position within the open-source and cryptographic communities. While Matter Labs has defended its actions as protective measures, the repeated controversies suggest a need for more transparent and community-aligned practices. The outcome of the BANKEX lawsuit could further influence Matter Labs' reputation and its relationship with the broader blockchain ecosystem.