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US 4259444Freedom to Build
Public domain since 1998

You can freely build on How Scientists Created Bacteria That Eat Oil Spills

This patent expired in 1998. 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

General Electric Co

Patent granted

1981

Expired

1998

Forward citations

28

What this patent covers

The patent describes a method for creating bacteria from the genus Pseudomonas that contain multiple stable 'plasmids.' These plasmids act like genetic toolkits, each providing the bacteria with a specific pathway to break down different types of hydrocarbons found in crude oil. By combining these plasmids into a single cell, the bacteria can digest a wider variety of oil components than they could in nature. For example, a single bacterium can be engineered to simultaneously possess the genetic instructions to degrade camphor, octane, salicylate, and naphthalene.

What is now free to use

All 0 claims of US 4259444 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 naturally occurring bacteria that have not been genetically modified to contain multiple stable plasmids.

    • Does not cover the degradation of non-hydrocarbon pollutants like heavy metals or plastics.

    • Does not cover methods of oil cleanup that do not involve the use of these specific multi-plasmid Pseudomonas strains.

    • Does not cover genetic engineering techniques applied to organisms outside the genus Pseudomonas.

    Who is building on this today

    General Electric was the original assignee, but the technology paved the way for modern synthetic biology companies like Ginkgo Bioworks and Amyris. These firms now use advanced CRISPR and metabolic engineering to design microbes for industrial applications far beyond simple oil degradation.

    Products built on expired version of this technology

    Bioremediation agents for cleaning up oil spills in marine environments

    Experimental oil-degrading bacterial cultures used in environmental cleanup research

    How to cite this patent in your documentation

    General Electric Co. US Patent 4259444. Microorganisms having multiple compatible degradative energy-generating plasmids and preparation thereof. Granted 1981, expired 1998. 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.

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