Shane Bryant, 30, from Birmingham, died in hospital on Saturday after being taken ill during a supermarket raid in Ashby-de-la-Zouch, Leicestershire.
North Leicestershire's coroner was told further tests were being carried out to establish the cause of death.
Mr Bryant's inquest has been opened and adjourned until 10 October.
The armed raid at a Co-operative store took place on 13 July.
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A 24-year-old man arrested on suspicion of causing grievous bodily harm has been released from custody pending further inquiries.
Witnesses claimed the arrested man was among a group of bystanders who intervened as two offenders, armed with a bat and a golf club, tried to flee the scene of the raid.
Coroner Trevor Kirkman said: "I have a statement from Stephen Belcher, of Derbyshire Constabulary, who confirms that on 15 July he examined a number of fingerprints and was able to establish from corresponding prints that the deceased was Shane Bryant."
Detectives are appealing for mobile phone footage of the robbery and its aftermath.
The Independent Police Complaints Commission has started an investigation into the death.
A suspected robber who died in hospital after being restrained by members of the public has been identified by his fingerprint records, an inquest hears.