You can freely build on How A.C. Gilbert Designed Early Interlocking Toy Construction Blocks
This patent expired in 1933. 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
MYSTO Manufacturing CO
Patent granted
1913
Expired
1933
Forward citations
3
What this patent covers
This patent describes a mechanical system for toy construction blocks that feature specific interlocking mechanisms. The design allows individual blocks to be joined together securely to form larger, stable structures. By utilizing specific protrusions and corresponding recesses on the surfaces of the blocks, the system enables children to build models that hold their shape during play.
What is now free to use
All 0 claims of US 1066809 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 modern plastic bricks that use friction-fit studs like LEGO
Does not cover electronic or motorized construction sets
Does not cover non-interlocking stacking blocks like wooden cubes
Who is building on this today
Modern toy companies like LEGO and various STEM-focused educational toy startups have evolved these early modular construction concepts into highly complex, precision-engineered plastic systems.
Products built on expired version of this technology
Early 20th-century wooden construction block sets
Mysto Manufacturing toy kits
How to cite this patent in your documentation
MYSTO Manufacturing CO. US Patent 1066809. Toy construction-blocks.. Granted 1913, expired 1933. 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.