The European Union’s (EU) highest court Thursday ruled that the zero-tariff plans offered by internet access providers are contrary to the regulations on Open Internet Access and incompatible with EU law.

Zero-tariff is a commercial plan offered to attract customers in which data used on specific applications offered by partners of that access provider will not be counted as part of the basic package. It is said to be anti-competitive because it goes against the “level playing field” principle of open internet/net neutrality.

The question of zero-tariff compatibility with the EU law was brought before the Luxembourg-based EU Court of Justice (CJEU) by two German courts against internet access providers Vodafone and Telekom Deutschland.

The court held that the zero-tariff practice “is contrary to the general obligation of equal treatment of traffic, without discrimination or interference, as required by the regulation on open internet access”. Additionally, since limitations on bandwidth. tethering or on use when roaming applies only when the zero-tariff option is activated, they are also incompatible with EU law.

The principle of open internet or net neutrality was codified by the European Parliament through Open Internet Regulations in 2015.  The issue with these regulations is that the provisions are vague and subject to misuse. As a result, many providers continued with the zero-tariff practice leading to questions testing the robustness of the law. After the judgement of the CJEU, providers cannot impose any limitations hence the promotion of consumer choice, competition, innovation, media diversity and freedom of information will continue.

This is the second time the CJEU has ruled against zero-tariff practices. Last year, the court handed a similar judgement against Telenor in a challenge by a Hungary court.