France's top court scrapped multiple provisions of an anti-hate speech law on the grounds that it violated the constitution.
The law, which was passed and adopted by France's parliament last month, required online platforms and search engines to remove hateful or terrorist content within 24 hours of it being posted, risking fines of up to €1.25 million.
A second provision of the law required child pornography to be removed within one hour of being posted, after notification.
France's constitutional council - a court that determines whether laws respect the country's constitution - said the law infringed on free speech and did not give operators enough time to locate material remove it or get a judge's opinion on content.
"Freedom of expression and communication is all the more precious since its exercise is a condition of democracy and one of the guarantees of respect for other rights and freedoms," the court said in a statement.
The court determined that the law "infringes upon freedom of expression" in a manner that is not "necessary or proportionate" to the law's purpose.
The decision is a blow to Emmanuel Macron's centre-right party that hoped the law would be a model for tackling hate speech.
It was proposed by French parliamentarian Laeticia Avia, who is a member of Macron's political party.
Avia said in a statement after the court's decision that she would not "give up the fight to protect Internet users, victims or witnesses of online hatred".
Critics have said the law went too far and the challenge to the legislation was brought forth by Republican Senators.
"We too often make bad laws with good intentions. Online platforms should not censor the freedom of expression," said Chairman of the Senate Law Commission Philippe Bas who called the court decision "wise".