Patent Expiration Calculator
Protect your invention timeline. Calculate when your patent expires and plan for the transition to public domain or renewal strategy.
Enter your contract details
The date you filed the patent application
Length of patent protection (typically 20 years from filing)
Frequently Asked Questions
Common questions about patent expiration calculator
Utility patents expire 20 years from the filing date. Design patents last 15 years from grant. Plant patents last 20 years. Maintenance fees must be paid to keep patents active.
In most countries, utility patents last 20 years from filing date. However, you must pay maintenance fees at 3.5, 7.5, and 11.5 years (US) to keep the patent in force.
Generally no. Patent terms are fixed by law. Some exceptions exist for pharmaceutical patents (patent term extension) or delays in prosecution, but standard extensions are not available.
The invention enters the public domain. Anyone can use, make, or sell the invention without permission or royalty payments. This is why generic drugs become available after pharma patents expire.
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