A former sub-postmaster wrongly jailed in the Horizon scandal has called for the Welsh government to terminate its contracts with Fujitsu.
Hundreds of sub-postmasters were prosecuted when the faulty Horizon computer system wrongly showed money missing from Post Office branches.
Fujitsu, which developed and operated Horizon, has apologised for its role in the scandal.
Former sub-postmaster Noel Thomas, from Anglesey, was one of those jailed.
He was locked up in 2006 after being given legal advice to plead guilty to false accounting.
Three years ago his conviction was overturned.
Now Newyddion S4C has found millions of pounds of Welsh taxpayers' cash has been been spent on Fujitsu contracts since the High Court brought the company's failings to light.
It ruled in 2019 Horizon was faulty, and had led to wrongful prosecutions by the Post Office.
Mr Thomas said he wanted Welsh public contracts with Fujitsu terminated.
The Welsh government confirmed it was the contracting authority for two contracts for Transport for Wales (TfW) ticketing systems, worth more £2m, which were awarded in August 2022.
That was almost a year-and-a-half after Mr Thomas and 38 others had their names cleared at the High Court in London.
Mr Thomas said he was "disappointed" Fujitsu had been given more contracts.
He said he wanted Fujitsu's contracts terminated "after all the bother they've caused, which for me has lasted 20 years".
He added: "Why have they gone down this road? Fujitsu seem to have contracts everywhere.
"It is surprising these contracts are still in place."
Fujitsu said it was suspending bidding for UK public contracts until after the public inquiry into the scandal had ended.
It has not answered the question of whether this includes Welsh government contracts.
In Westminster, the Commons Treasury Committee has written to 21 public bodies asking for details of any contracts with Fujitsu since December 2019.
According to Tussell.com current UK public contracts with Fujitsu are worth £6.8bn.
The Welsh government was asked if Fujitsu would be allowed to bid to have contracts renewed when they expire in July.
It said: "Legislation makes it possible for public sector buyers to exclude a bidder from a procurement process if they are considered to be subject to one or more exclusion grounds as laid out in the legislation."
A contract worth £1m a year between Fujitsu and TfW, was extended for two years in April last year without a tender process.
TfW is a Welsh government-owned not-for-profit company.
It told Newyddion S4C extending the contract without giving other companies the opportunity to bid for it "was deemed to be more cost effective than replacing the existing hardware".
The Welsh government said: "This is an operational contract for Transport for Wales in which Welsh government has no involvement."
Plaid Cymru transport spokeswoman Delyth Jewell said: "This is public money. I'd like to see more diligence and a review into how those contracts have been awarded.
"I think many people in Wales would say it is morally questionable whether a company which has played such a crucial role in destroying people's lives should be a fit and proper company to be getting public money."
Fujitsu said offered its "deepest apologies" to sub-postmasters and their families.
"The UK statutory public inquiry, to which our UK subsidiary is providing full cooperation, is examining complex events that have unfolded over many years, and we remain steadfast in our commitment to this cooperation.
"Based on the findings of the inquiry, we will also be working with the UK government on the appropriate actions, including contribution to compensation.
"The Fujitsu Group hopes for a swift resolution that ensures a just outcome for the victims."