The recent appellate decision in the long-running lawsuit brought by record labels and music publishers against MP3Tunes didn’t get a tremendous amount of attention, but Google, Facebook, eBay, Twitter and other digital giants are aghast at the result and warning of dire consequences without a do-over.

On Oct. 25, the 2nd Circuit Court of Appeals gave copyright holders some big victories by narrowing the circumstances whereby internet service providers can claim safe harbor from copyright liability.

MP3Tunes has now filed a motion for a rehearing en banc, and the company is being supported by friends in the tech industry. An amici curiae brief filed Tuesday on behalf of some of the largest online service providers is authored by noted legal scholar and advocate Mark Lemley and points to “three things” that “could be read to require OSPs to act in ways that are socially undesirable and technically infeasible.”

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“Amici are concerned that some will read this to suggest that OSPs must identify as repeat infringers not only users who repeatedly post infringing content … but also anyone who interacts with content that is later alleged to be infringing, including those who merely access it or refer to it using a hyperlink,” writes Lemley. “That would wreak havoc on the routine practices of OSPs far removed from MP3Tunes. For example, it might require companies like Yahoo!, Google and Pinterest to force their users to log in so they can track their activity and require termination of huge numbers of internet users who have never been accused of copyright infringement.”

Lemley argues that DMCA takedown notices are standard protocol for figuring out who is an infringer.

“It is entirely different, however, to impose on OSPs an obligation to tally strikes and terminate users merely for having accessed, viewed, or otherwise engaged with content that later might be the subject of a takedown notice,” he adds. “That would upend existing practices for responsible OSPs that host user-submitted material. On this view, a repeat infringer would be not just one who serially causes infringing content to be stored on a provider’s system, but potentially anyone who has ever come into contact with that content.”