The Central London Community Healthcare NHS Trust has confirmed it intends to issue a legal challenge to the Information Commissioner's Office's (ICO) £90,000 fine, claiming it had acted responsibly with patient data.
The ICO announced its intention to issue the fine on Monday but the Trust confirmed it has already begun work to challenge the penalty.
"We deeply regret that the information commissioner has decided to impose a fine and so we have instructed our lawyers to commence an appeal against this," it said.
"We consider that the commissioner has acted incorrectly as a matter of law and so we have no alternative but to bring an appeal."
The organisation also repeated apologies that the incident had occurred.
"It is hugely regrettable that this incident, which was down to human error, happened and we have apologised to all the individuals and families who were affected by this mistake," read the statement.
An ICO spokesperson said that the Trust had been made aware of the loss by the unintended recipient, who reportedly received around 45 faxes containing medical diagnoses and information relating to patients domestic situations and resuscitation instructions over a three month period.
The ICO issued a similar fine to the London Borough of Barnet after it lost records containing confidential information on a number of vulnerable children.
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