# Public domain

The status of an invention (or creative work) that is no longer — or never was — protected by any intellectual property rights, meaning anyone can use it freely. Patents enter the public domain after expiration (typically 20 years from filing for utility patents). Expired patents represent a vast, free library of technology available to all. Many foundational technologies — aspirin, the original CRISPR patents — have entered or are approaching the public domain.

**Full entry:** https://patentbrief.org/glossary/public-domain

**All patent terms:** https://patentbrief.org/glossary

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_Source: PatentBrief — https://patentbrief.org. A plain-English glossary of US patent terms._