Apple, Google and Microsoft have been whacked with a US court order by Tesla that forces them to preserve copies of an ex-employee's deleted emails and cloud storage accounts.

Tesla alleges that former Gigafactory process technician Martin "Marty" Tripp "exported confidential and trade secret information" from the struggling carmaker by uploading it "to his personal email and cloud storage accounts".

Elon Musk's company is now pursuing Tripp through the American courts over what it says is his theft of trade secrets – and it wants the three big dogs of tech to preserve Tripp's deleted digital doings for potential future use as "critical evidence of [his] unlawful activities".

American law allows parties trying to sue each other to have the contents of online accounts preserved by providers in case they are wanted in a later trial. Some will do so voluntarily; many others ask to see a court warrant before doing so.

Tripp, according to Tesla's court filings, "wrote specialised software designed to export confidential and trade secret information from Tesla's manufacturing operating system" and sent the info he supposedly slurped to unspecified "outside entities". Another Tesla employee, Andrew Lindemulder, declared in writing to the court that Tripp had confessed to him that he had deleted material to "cover [his] tracks".

Apple had rebuffed Tesla's direct approaches, telling the carmaker it "will not preserve evidence in response to your request absent service of appropriate legal process". Microsoft blanked Tesla, while Google was served with a copy of the subpoena but did not appear, from court filings, to have been asked to voluntarily comply beforehand.

Magistrate Valerie Cooke, sitting in the American Federal District Court for Nevada, USA, granted Tesla's application for document preservation subpoenas on Tuesday 26 June. The order means the contents of Tripp's email accounts stretching back to 1 October 2017, as well as his Onedrive, Sharepoint and iCloud storage accounts over the same period, will be preserved.

Although Tesla had prepared subpoenas against Facebook, Dropbox, Open Whisper, Signal, AT&T and Whatsapp, it only went ahead with those for Apple, Google and Microsoft.

Tripp had not made any legal filings in response to the Tesla lawsuit by the time of writing. The firm is pursuing $1,000,000 in damages.

Microsoft in the UK does demand court warrants before granting access to email accounts, even those of the dead. The Register attended one such case before the High Court in London where the American firm had taken no position other than to say "please show us a court order". ®