You can freely build on How Computers Automatically Label Different Speakers in Audio Recordings
This patent expired in 2019. 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
International Business Machines Corp
Patent granted
2002
Expired
2019
Forward citations
75
What this patent covers
This system processes audio to identify who is speaking by breaking the audio into segments and comparing them against a database. It uses 'background models' for people not yet in the system, such as a generic 'unenrolled male' or 'unenrolled female' profile. When the system detects a recurring voice that it doesn't recognize, it groups those segments together into a cluster. A user can then provide a name for that cluster, and the system automatically updates its database to recognize that person in future recordings.
What is now free to use
All 0 claims of US 6424946 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 real-time voice synthesis or voice modification.
Does not cover hardware-based microphones or physical audio capture devices.
Does not cover methods that require every speaker to be pre-enrolled before identification can begin.
Does not cover the specific linguistic analysis of the words being spoken, only the identification of the speaker.
Who is building on this today
IBM remains a significant player in enterprise AI and natural language processing. Modern cloud providers like Amazon (AWS Transcribe), Google (Cloud Speech-to-Text), and Microsoft (Azure Speech) have expanded these foundational clustering techniques into massive, scalable services.
Products built on expired version of this technology
Automated meeting transcription services like Otter.ai
Zoom and Microsoft Teams speaker identification features
Legal and medical transcription software
Call center analytics platforms
How to cite this patent in your documentation
International Business Machines Corp. US Patent 6424946. Methods and apparatus for unknown speaker labeling using concurrent speech recognition, segmentation, classification and clustering. Granted 2002, expired 2019. 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.