Anish Kapoor provoked the fury of fellow artists by acquiring the exclusive rights to the blackest black in the world.

Known as Vantablack, the material is so dark that it absorbs 99.96 percent of light. It was created in 2014 by the UK firm Surrey NanoSystems and was developed for military purposes such as the painting of stealth jets.

The Indian-born British artist has been working and experimenting with the “super black” paint since shortly after its invention, and has recently acquired exclusive rights to the pigment according to reports by the Daily Mail.

A sample of Vantablack. The material is so dark it makes crinkled aluminum foil appear flat. Photo by Surrey NanoSystems Creative Commons Attribution-Share Alike 3.0 Unported license.

“It’s blacker than anything you can imagine,” Kapoor told BBC radio 4 in September 2014. “It’s so black you almost can’t see it. It has a kind of unreal quality.”

The artist clearly knows the value of this innovation for his work. “I’ve been working in this area for the last 30 years or so with all kinds of materials but conventional materials, and here’s one that does something completely different,” he said, adding “I’ve always been drawn to rather exotic materials.”

However, Kapoor’s decision to withhold the material from fellow artists has sparked outrage across the international artists community.

The British painter Christian Furr angrily told the Daily Mail “I’ve never heard of an artist monopolizing a material […] We should be able to use it. It isn’t right that it belongs to one man.”

The Indian Telegraph cited Kapoor’s fellow British Indian artist Shanti Panchal who also criticized Kapoor. “I have not known of anything so absurd,” he said. “In the creative world, artists, nobody should have a monopoly.”

Some have taken to social media to criticize Kapoor. One Twitter user joked “Anish Kapoor’s narcissism rises to 99.96% as he’s given exclusive rights to Vantablack.” Another user simply said “This is immoral, surely?”

Yet the case isn’t unprecedented. In 1960, Yves Klein invented a color and secured a patent on International Klein Blue. The difference is that Kapoor didn’t invent Vantablack, and that Vantablack’s properties are very unique.

Anish Kapoor declined to comment on his acquisition of Vantablack, and Surrey NanoSystems didn’t respond to a request for comment.