EFF warns Texas Instruments to stop harassing calculator hobbyists

The Electronic Frontier Foundation (EFF) warned Texas Instruments (TI) not to pursue its baseless legal threats against calculator hobbyists who blogged about potential modifications to the company’s programmable graphing calculators.

TI’s calculators perform a “signature check” that allows only approved operating systems to be loaded onto the hardware. But researchers were able to reverse-engineer signing keys, allowing tinkers to install custom operating systems and unlock new functionality in the calculators’ hardware.

In response to this discovery, TI unleashed a torrent of demand letters claiming that the anti-circumvention provisions of the DMCA required the hobbyists to take down commentary about and links to the keys. EFF represents three men who received such letters.

“The DMCA should not be abused to censor online discussion by people who are behaving perfectly legally,” said Tom Cross, who blogs at memestreams.net. “It’s legal to engage in reverse engineering, and its legal to talk about reverse engineering.”

In fact, the DMCA explicitly allows reverse engineering to create interoperable custom software like the programs the hobbyists are using. Additionally, TI makes its software freely available on its website, so there is no connection between the use of the keys and unauthorized distribution of the code.

“This is not about copyright infringement. This is about running your own software on your own device — a calculator you legally bought,” said EFF Civil Liberties Director Jennifer Granick. “Yet TI still issued empty legal threats in an attempt to shut down discussion of this legitimate tinkering. Hobbyists are taking their own tools and making them better, in the best tradition of American innovation.”