You can freely build on How the First Automatic Implantable Defibrillator Works
This patent expired in 1990. Every claim — 0 independent, 0 dependent — is now unenforceable. Anyone can use, reproduce, manufacture, sell, or offer for sale this technology without a license.
Original assignee
Medtronic Inc
Patent granted
1971
Expired
1990
Forward citations
71
What this patent covers
The device acts as a continuous heart monitor that tracks electrical activity to identify life-threatening arrhythmias. When the system detects an abnormal heart rhythm, it triggers a high-voltage discharge to shock the heart back into a normal sinus rhythm. If the first shock fails to restore normal function within a set interval, the mechanism is designed to deliver subsequent shocks. The device remains inactive as long as the heart's electrical activity stays within normal parameters.
What is now free to use
All 0 claims of US 3614954 are in the public domain. Specifically:
The 0 dependent claims add narrowing limitations and are also free.
What is NOT covered
Patent expiry frees this specific invention. Separately-patented improvements made after expiry may still be protected.
Does not cover external defibrillators that require manual operation by a human.
Does not cover devices that monitor blood pressure or oxygen levels rather than electrical heart activity.
Does not cover pacemakers that only provide low-voltage stimulation for slow heart rates.
Who is building on this today
Medtronic remains a dominant force in this space, having commercialized the technology derived from this early work. Other major medical device companies like Boston Scientific and Abbott Laboratories continue to advance ICD technology with smaller leads and smarter sensing algorithms.
Products built on expired version of this technology
Modern implantable cardioverter-defibrillators (ICDs)
Subcutaneous ICDs (S-ICD)
How to cite this patent in your documentation
Medtronic Inc. US Patent 3614954. Electronic standby defibrillator. Granted 1971, expired 1990. Now in the public domain.
Note: This is a convenience citation. Consult a patent attorney for formal freedom-to-operate analysis.
PatentBrief is an educational resource and does not provide legal advice. Patent expiration information is derived from USPTO records and may not reflect continuation patents, divisional filings, or separately-patented improvements. For commercial use or production decisions, obtain a formal freedom-to-operate (FTO) opinion from a registered patent attorney.