The failure of Railtrack shareholders to win compensation from the government was "almost inevitable", former rail regulator Tom Winsor has said.
Mr Winsor said the rail system has improved since Railtrack's demise
Shareholders were unable to persuade a judge that former Transport Secretary Stephen Byers acted maliciously and actively sought the firm's collapse.
Asked about the ruling, Mr Windsor said it was "abundantly clear" that Mr Byers had not acted maliciously.
Railtrack went into administration in October 2001.
The government had withdrawn the company's funding in the aftermath of the fatal Hatfield crash in 2000.
Both Mr Byers and the government had always denied any wrongdoing.
Despite the failure of the shareholders' £157m compensation case, Mr Byers could yet face censure from the House of Commons.
During the trial it was revealed that he had earlier misled a Commons sub-committee.
Speaking at the High Court on Friday, Mr Justice Lindsay said it was for Parliament, and not him, to decide whether Mr Byers was a liar or not.
"His explanation as then given seems to me little above gibberish, but it will be for Parliament to assess what he meant," said the judge.
"I do not find Mr Byers generally to have been an untruthful witness."
Mr Winsor said the injury to shareholders was a "by-product" of Mr Byers' actions, rather than the reason for his behaviour.
However, the former regulator argued that Mr Byers had been guilty of "political impatience", adding that the government "jumped the gun" by putting the company into administration.
Stephen Byers has described the verdict as 'a great victory'
Mr Winsor said: "Railtrack was a seriously unsatisfactory company. It had a hostility to its customers...[and]...it had a policy of neglect of its assets - it didn't have cost control."
He added: "We do now have an improved railway system.
"We do have sharply falling costs, significantly improved efficiency, much better punctuality and reliability and some of the best track quality results and measures in Europe."
However, he said these improvements were not necessarily due to Mr Byers' actions, but industry reforms and improved management.
Mr Byers described the verdict as "a great victory".
"The Railtrack shareholders put my honesty and integrity at the heart of their case and the court has found in my favour," he said in a statement after the court ruling.
"This legal action was a political attack on my decision to deny Railtrack yet more taxpayers' money. Throughout this whole affair I have put the public interest first."
The civil lawsuit was brought by the 49,000-strong Railtrack Private Shareholders Action Group, in the name of retired Railtrack engineer Geoffrey Weir.
Geoffrey Weir said the shareholder group may now appeal
Mr Weir said the shareholders were now considering whether they had grounds for appeal after being "disappointed and perplexed" by the ruling.
Under cross-examination by MPs, Mr Byers was asked if he had begun discussing the demise of Railtrack before a key meeting in July 2001, at which the company's chairman warned Mr Byers of the financial difficulties.
Mr Byers told MPs that he had not, but during the High Court case he admitted "it is true to say there was work going on, so yes that was untrue".
Railtrack was replaced by not-for-profit company Network Rail in 2002.
Railtrack was formed in April 1994 after the privatisation of the UK railway network by the then Conservative government of John Major.
Many small investors snapped up shares when it floated on the London Stock Exchange in 1996.
The group's shares climbed as high as 1768 pence each, but were eventually suspended at 280p each when it went into administration in 2001.
Institutional shareholders accepted the government's eventual compensation offer of about 250p a share, but the private shareholders wanted much more.