Skip to content
PatentBrief
US 5013088Freedom to Build
Public domain since 2009

You can freely build on How Tamper-Proof Labels That Break Into Pieces Work

This patent expired in 2009. 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

Data Tech Services Inc

Patent granted

1991

Expired

2009

Forward citations

23

What this patent covers

The patent describes a label made of opaque paper with a special adhesive that sticks to documents. The key feature is a series of pre-cut patterns, specifically radial cuts or interlocking rings, that weaken the label's structure. When someone attempts to peel the label off the document, these cuts ensure the label tears into small, unusable fragments rather than coming off in one piece. This leaves clear evidence that the label was tampered with, while the underlying document remains intact.

What is now free to use

All 0 claims of US 5013088 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 labels that use chemical color-changing reactions to show tampering.

    • Does not cover labels that leave a 'VOID' pattern on the surface when removed.

    • Does not cover labels made of non-paper materials like plastic or metallic foils.

    • Does not cover adhesive systems that require heat or light to activate or deactivate.

    Who is building on this today

    The technology is fundamental to the physical security and document management industries. Companies specializing in security printing and tamper-evident packaging materials continue to refine these mechanical failure patterns for modern document redaction.

    Products built on expired version of this technology

    Security masking labels on sensitive legal documents

    Tamper-evident seals on private medical records

    Redaction stickers used in document processing

    How to cite this patent in your documentation

    Data Tech Services Inc. US Patent 5013088. Disintegratable masking label. Granted 1991, expired 2009. 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.

    ← Full patent detailsMore public domain patents →