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The short answer is that ARKs are the only mainstream, non-siloed, non-paywalled identifiers that you can register to use in about 24 hours. DOIs, Handles, and PURLs require resolution and other services to come from their respective centralized systems (silos).
ARKs are very unusual in being decentralized. While one can get resolution services from a global ARK resolver called n2t.net, over 90% of the ARKs in the world do not use it.
More than Over 500 registered organizations across the world have created an estimated 3.2 billion ARKs in the world, and no one has ever paid for the right to create them.
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