An amendment to the 2027 budget would charge every company that sends data to French internet subscribers €0.055 per gigabyte, and its Socialist authors expect it to raise €10 billion a year.

But by Sunday, someone had turned the tax on the party that wrote it. 

An internet user put a 44MB PDF from the Socialist Party's website on a server on his own machine, downloaded it in an endless loop and tallied the tax the traffic would generate: 13,109 downloads, 576 gigabytes and €31.70 in under four hours.

In the simulation, the counter shows the loop running from a local address, 127.0.0.1, so no traffic reached the party's servers and no internet provider metered a byte. The math matches the amendment's rate, though: 576.4 gigabytes at €0.055 comes to €31.70.

The potential damage could be huge. VideoLAN, the French nonprofit behind the VLC media player, said the tax would cost it more than €1 million a year - as the amendment doesn't say how its revenue-based cap would apply to a nonprofit that earns little.

The roll call shows how slim the majority was. Only 35 deputies voted, 11 in favor, 10 against and 14 abstaining, and the amendment was adopted on Oct. 30 on the strength of its 11. National Rally's 10 deputies abstained, and had they voted no, the amendment would have failed 20 to 11. The yes votes came from five Socialists, two members of La France Insoumise, two Greens and two from the Democratic and Republican Left. All 10 votes against came from the center and the right: four from Ensemble pour la République, five from Droite Républicaine and one from Les Démocrates. Four of La France Insoumise's deputies also abstained.

The text was filed Oct. 9 by Socialist Laurent Lhardit and dozens of his colleagues, former President François Hollande among them. It would make the "content provider" that sent the data, not the internet provider, liable for the tax, which it calls a tax on digital data producers. Internet providers would be required to meter every sender's traffic into French homes and businesses under the supervision of the telecom regulator Arcep and the tax administration, and report the totals to the tax authority each quarter. The amendment bars collecting anything about what the data contains or where it goes. When a sender uses a content delivery network, the volume counts as everything leaving that network. The details of the metering would be left to a government decree.