How Gideon Sundback Invented the Modern Zipper
The 1917 patent for the separable fastener that perfected the design of the modern zipper using interlocking teeth on two flexible tapes.
Original patent title: “Separable fastener.”
The 1917 patent for the separable fastener that perfected the design of the modern zipper using interlocking teeth on two flexible tapes. Granted to Hookless Fastener Co in 1917 with 14 forward citations, and it is now in the public domain.
Coverage
What does this patent actually cover?
This patent describes a mechanism for joining two edges of fabric using a series of interlocking teeth mounted on flexible tapes. The device uses a sliding cam, or slider, to force the teeth together when moving in one direction and to pry them apart when moving in the other. By alternating the position of the teeth and using a specific spring-loaded locking mechanism, the fastener ensures that the teeth remain securely engaged even when under tension.
The gap
What does this patent NOT cover?
- Does not cover non-interlocking fasteners like buttons, hooks, or snaps.
- Does not cover magnetic or adhesive-based fastening systems.
- Does not cover zippers that use continuous coils instead of individual metal teeth.
These exclusions are unique to PatentBrief — derived from the actual claim language, not patent-office boilerplate.
Key facts
What made this novel
The innovation was the precise geometry of the teeth and the slider's internal channels, which allowed for a smooth, reliable engagement that didn't pop open under the natural stress of movement.
The Patent Drawing
Schematic visualization of the patent's claim structure. Hand-drawn diagrams in progress for each landmark patent.
Where you've seen this
Real-world examples
Standard metal zippers on denim jeans
Fasteners on heavy-duty canvas bags
Military-grade gear and field equipment
Why it matters
The bigger picture
Before this design, early attempts at slide fasteners were unreliable and prone to jamming. Gideon Sundback's refinement turned a niche industrial curiosity into a ubiquitous consumer product, fundamentally changing how we manufacture clothing, luggage, and footwear.
Filed
August 27, 1914
Granted
March 20, 1917
Market context
Who's building on this
Companies in this space
The Hookless Fastener Company eventually became YKK, which remains the dominant global manufacturer of fastening systems today. Many modern textile manufacturers continue to utilize the fundamental mechanical principles established in this 1917 patent.
Market impact
This patent effectively standardized the zipper, enabling the mass production of garments that required quick and secure closure. It eliminated the need for complex buttoning systems in high-wear applications and created the multi-billion dollar global fastener industry.
Claim 1 — Plain English
What this patent covers
This patent describes a mechanism for joining two edges of fabric using a series of interlocking teeth mounted on flexible tapes. The device uses a sliding cam, or slider, to force the teeth together when moving in one direction and to pry them apart when moving in the other. By alternating the position of the teeth and using a specific spring-loaded locking mechanism, the fastener ensures that the teeth remain securely engaged even when under tension.
The clever bit
The innovation was the precise geometry of the teeth and the slider's internal channels, which allowed for a smooth, reliable engagement that didn't pop open under the natural stress of movement.
What it does not cover
- Does not cover non-interlocking fasteners like buttons, hooks, or snaps.
- Does not cover magnetic or adhesive-based fastening systems.
- Does not cover zippers that use continuous coils instead of individual metal teeth.
Patent timeline
Application submitted to the patent office
Application published, typically 18 months after filing
Patent officially issued
Patent enters public domain
This patent is in the public domain
See the Freedom to Build guide — what is free to use, what is not, and how to cite this patent.
PatentBrief Score
Impact Score
Early stage
Citation count
23/40
Moderately cited
Claim breadth
0/20
Narrow claimsclaimsThe numbered statements at the end of a patent that legally define what the inventor owns.Read more →
Recency
0/20
Older than 20 years
Assignee scale
0/20
Independent or smaller assigneeassigneeThe entity that owns the patent — usually the inventor's employer or a company.Read more →
PatentBrief Impact Score — based on citation count, claim breadth, recency, and assignee scale. Not a legal assessment.
Heuristic Value Estimate
What this patent might be worth
$8K – $25K
Midpoint $15K · expired or expiring · industry ×1.6
Heuristic only — blends forward/backward citation counts, claim scope, time remaining, litigation history, and CPC-derived industry baseline. Real valuations need a professional appraisal.
Claim text not yet imported for this patent
Concepts involved
Citations
Patent lineage
Cite this patent
Sundback, G. (1917). How Gideon Sundback Invented the Modern Zipper (U.S. Patent No. 1,219,881). U.S. Patent and Trademark Office. https://patentbrief.org/patent/us/1219881/zipper-separable-fastener
Auto-generated from the patent record. Double-check author order and the issue date against the official USPTO document before submitting.
Embed
Add this patent to your site
Drop this plain-English patent card into any blog post or article — free, no signup. It always links back to the full breakdown here.
<div data-patentlens-widget data-patent-number="US1219881"></div> <script src="https://patentbrief.org/embed.js" async></script>
Stay in the loop
Get a weekly digest of new patents.
One email per week. No spam. Unsubscribe anytime.
Keep exploring
Related patents you should know
US 4683195 · 1987
How to Make Billions of Copies of a DNA Segment
This patent describes the Polymerase Chain Reaction (PCR), a method to rapidly create many copies of a specific piece of DNA or RNA, enabling its detection and analysis.
Cetus Corp
US 8697359 · 2014
How to Edit Genes in Human Cells Using an Engineered CRISPR System
This patent describes an engineered CRISPR-Cas9 system for precisely cutting DNA in eukaryotic cells to change how genes work, opening the door for gene editing in complex organisms.
Massachusetts Institute of Technology
US 7657849 · 2010
How the iPhone's Slide-to-Unlock Gesture Works
Apple's 2010 patent describes unlocking a device by dragging a specific graphical image across the touchscreen along a predefined path, a gesture that became iconic with the original iPhone.
Apple Inc
US 4733665 · 1988
How Doctors Implant a Permanent Stent Using a Balloon
This patent describes the method for placing a permanent, expandable wire mesh tube inside a blood vessel or other body tube using a balloon-tipped catheter to widen it and keep it open.
Expandable Grafts Partnership
US 4965188 · 1990
How to Make Many Copies of a DNA Piece with Heat
This patent describes the Polymerase Chain Reaction (PCR) method, a technique to make millions of copies of a specific DNA segment using a heat-resistant enzyme and repeated temperature changes.
Cetus Corp
US 4235871 · 1980
How to Encapsulate Active Materials in Lipid Bubbles Efficiently
This patent describes a method for trapping biologically active substances inside tiny, multi-layered fat bubbles called liposomes, using a specific water-in-oil emulsion and gel-forming process to improve how much material gets captured.
Individual
Semantically similar
You might also find these interesting
US 139121 · 1873 · Levi Strauss & Co.
How Levi Strauss Invented the Copper-Riveted Jean Pocket
US 775134 · 1904 · FED TRUST Co
How King Gillette Invented the Modern Disposable Safety Razor
US 3349949 · 1967
The Invention of the Modern Soda Can Pull-Tab
US 4750 · 1846 · Elias Howe
How Elias Howe Invented the Modern Lockstitch Sewing Machine
More to explore
More in Consumer Electronics
US 7657849 · 2010 · Apple Inc
How the iPhone's Slide-to-Unlock Gesture Works
US 7479949 · 2009 · Apple Inc
How Touchscreens Understand Your Finger Swipes and Scrolls
US 4528643 · 1985 · FPDC Inc
How Stores Make Custom Products On-Demand with Remote Approval
US 7469381 · 2008 · Apple Inc
How Touchscreens Show and Snap Back When You Scroll Past an Edge
New to patents?
Common Questions
Frequently Asked Questions
What does How Gideon Sundback Invented the Modern Zipper cover?
The 1917 patent for the separable fastener that perfected the design of the modern zipper using interlocking teeth on two flexible tapes.
Who owns patent US 1219881?
Hookless Fastener Co owns this patent, granted in 1917.
When does this patent expire?
This patent has expired and is now in the public domain — anyone can use the invention freely.
What is patent US 1219881 cited by?
This patent has been cited by 14 later patents that build on its ideas.
What problem does this patent solve?
Before this design, early attempts at slide fasteners were unreliable and prone to jamming. Gideon Sundback's refinement turned a niche industrial curiosity into a ubiquitous consumer product, fundamentally changing how we manufacture clothing, luggage, and footwear.
What does this patent NOT cover?
Does not cover non-interlocking fasteners like buttons, hooks, or snaps.
Patent monitoring