The Ministry of Agriculture says there are no grounds to prosecute Plant & Food Research, following an investigation into possible containment breaches of a genetically modified plant.
In November last year, two genetically modified brassica plants were found growing outside a containment glasshouse at a Lincoln site used by Plant & Food.
Acting MAF deputy director general of compliance Warwick Foran says an investigation into the breach, found Plant & Food took reasonable care and was not negligent in its work.
He says the organisation complied with all the procedures and standards set out in its consent conditions.
Mr Foran says MAF were also unable to determine a cause of the GM escape.