BERLIN (AP) — Yahoo says it has filed a complaint to Germany’s highest court against a year-old law that broadened copyright protection for news material used on the Internet.

The law aims to protect the copyright of news articles and other material on the Internet, but allows the use of “single words or small text passages” without royalties. Internet firms warned before it came into effect that it would amount to a tax on search engines.

Sunnyvale, California-based Yahoo Inc. said Friday that the vagueness of the rules and the resulting “unreasonable” legal uncertainty forced it to take the legislation to Germany’s Federal Constitutional Court. It argued that the law unconstitutionally limits Internet users’ freedom of information.

It wasn’t clear when the court might consider the complaint.

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