Circle says it didn’t copy Maple’s code for smart contracts

Executives at crypto credit protocol Maple Finance took to social media last week to vent about a new, competing product that they say was derived from their own.

Perimeter Protocol, a collection of smart contracts published by Circle — the company behind the USDC stablecoin — was “forked” from Maple, the company’s head of growth and capital markets, Quinn Thompson, said in a tweet.

“Imitation is the sincerest form of flattery,” co-founder Sid Powell wrote in his own tweet. “I’m sure the citation is somewhere in the footnotes.”

In a statement to DL News, Circle said it didn’t copy anyone’s code in making Perimeter.

“Circle Research built its inaugural open-source contribution, Perimeter Protocol, from scratch — without forking or copying code — to offer a new standard for others to build on-chain credit markets,” a spokesperson said. “Perimeter’s open-source code is available for all to see and verify.”

It wasn’t the only attribution complaint directed at Circle in the past week.

Last Sunday, James Prestwich, co-founder and CTO at crypto bridge Nomad, took to GitHub to flag Circle’s use of Nomad code in Circle’s cross-chain transfer protocol. Circle promptly updated that protocol’s code repository to provide proper attribution.

“My issue is completely procedural,” Prestwich wrote on X. “Re-use of open-source code is good, and it’s why I write open-source code.”

Open source and crypto

The code behind software products is often a closely guarded secret. That’s less true in crypto, where code is often open-source, meaning it can be used by anyone, for any reason. Copies of popular protocols — “forks,” in crypto parlance — are common.

When crypto protocols aren’t open-source, they are often protected by relatively lax licences, such as a Business Source License, which protects the code in question from being used and profited from by others for a certain period of time.

Moreover, in an industry in which the most popular applications are tied to finance, making code public is a matter of security, according to Benjamin Cole, a professor at Fordham University’s Gabelli School of Business.

“How can you trust a smart contract to not have vulnerabilities if you cannot see the code?” Cole told DL News. “This is another reason why open source has been a key pillar of blockchain since its beginning.”

The row is the latest to highlight disputes over authorship that arise when businesses’ software is published for the world to see.

In the past year, crypto venture capital firm Paradigm and Matter Labs, the company behind the zkSync blockchain, have been accused of copying others’ code. Both companies denied the accusations.

Like Maple, Perimeter is a credit protocol.

“With Perimeter, we are solving for how to bring real world assets and un-or-under collateralized loans with standards for underwriting and permissioning into a protocol we are offering as a public good,” Rachel Mayer, vice president of product at Circle, said in a blog post detailing Perimeter’s release.

Circle has made Perimeter Protocol itself open-source.

Maple’s case

Maple’s Thompson referred questions about the Circle accusations to Powell, who in turn declined to comment on the parts of Perimeter’s code they believe were forked from Maple. But Powell said Maple’s code was protected by a Business Source License.

“[The code] can’t be reproduced for commercial use without permission,” he told DL News. “But they can be reproduced for non-commercial use where they give attribution and use the same licence.”

Maple’s code, while protected, is available for anyone with an internet connection to peruse on GitBook. The code behind Perimeter Protocol has been published on GitHub, a popular code repository.

Because Maple’s code is not open-source, it could submit a “takedown request” for Perimeter’s code to Github, citing a Digital Millennium Copyright Act violation, according to Fordham’s Cole.

“This may eventually lead to a code-to-code comparison of overlap to prove the violation occurred,” Cole said.

Maple could also pursue Circle in court, relying again on a “line-by-line, code-to-code comparison,” according to Cole.

“This would be similar to when music artists sue each other for appropriating parts of a song, as recently happened with Ed Sheeran, who won his case by showing how prevalent certain chord progressions are in pop music and thus impossible to claim ‘copyright’ over,” Cole said.

“That would be Circle’s most obvious defence in court if pursued legally by Maple Finance —i.e., there are only so many ways to write smart contracts that perform certain functions,” Cole added.

Got a hot tip? Contact aleks@dlnews.com.