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US Patent Expiration Calculation:
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The US patent expiration date is typically 20 years from the patent's filing date. For patents filed before June 8, 1995, the term is either 20 years from filing or 17 years from issue, whichever is longer.
The calculator uses the standard patent term calculation:
Note: This calculation applies to utility patents filed on or after June 8, 1995. For design patents, the term is 15 years from issue for applications filed on or after May 13, 2015.
Details: Knowing the expiration date is crucial for determining when a patented technology enters the public domain and becomes available for unrestricted use by competitors.
Tips: Enter the patent issue date in YYYY-MM-DD format. The calculator will automatically add 20 years to determine the expiration date.
Q1: Are there exceptions to the 20-year rule?
A: Yes, patent term adjustments (PTA) or extensions (PTE) may extend the term beyond 20 years in certain cases.
Q2: How does this differ for international patents?
A: Other countries may have different patent term calculations. This calculator is specific to US utility patents.
Q3: What about maintenance fees?
A: While maintenance fees must be paid to keep a patent in force, they don't extend the maximum 20-year term.
Q4: How accurate is this calculator?
A: It provides the basic calculation, but for legal purposes you should verify with the USPTO or a patent attorney.
Q5: What happens after a patent expires?
A: The invention enters the public domain and can be freely used by anyone without permission.