A real estate agent who allegedly sent human faeces, used condoms and a headless rat to his former boss has been denied his bid for a licence reinstatement.

Grant Tucker was found guilty of disgraceful conduct in 2016, over the harassment of Custom Residential director Johnathan Wills and Wills' lawyer David Beard.

His license was cancelled by the Real Estate Agents Disciplinary Tribunal and this week as High Court appeal supported that decision.

Grant Tucker (above) allegedly sent offensive packages to a former boss and their lawyer

In addition to the vile packages, Mr Tucker was also accused of sending derogatory letters and emails according to The New Zealand Herald.

The offensive material was reportedly sent between 2014 and 2015, following his departure from Custom Residential.

The packages included one that contained human excrement and broken glass, while another supposedly contained a decapitated rat.

Mr Beard told the hearing during the August 2015 inquest that he had opened one box but was forced to stop and take it to police after he started to 'smell something vile'.

'Inside was what looked and smelled like human faeces. I was gagging over the side of Auckland Central Police Station,' he said.

Tucker was found guilty of disgraceful conduct in 2016, over the harassment of Custom Residential director Johnathan Wills (above) and Wills' lawyer David Beard

Mr Wills also received offensive material from Mr Tucker, who admitted tot he tribunal that he had left a message on his phone referring to him as a 'c**k-sucking f*****t'.

Mr Tucker launched an appeal in the High Court following the tribunal which was denied, with High Court Justice Sarah Katz stating ruling the licence cancellation would remain.

'It is clear that the sender of the parcels must have felt a high degree of animosity,' she said.

'The alternative scenarios advanced by Mr Tucker are simply implausible and are not supported by the evidence.'

Tucker began selling real estate in his early thirties, according to a biography from his former business NetRealty.

He had completed a Graduate Diploma in Business Studies and Postgraduate studies in Management and Commerce.

He also served as an Associate of the Real Estate Institute of New Zealand and had worked for Fletcher Homes, Vector and RE/MAX.