The High Court rejected a bid by the former leader for disclosure of documents that he claimed would help show he had been suspended from the parliamentary Labour party (PLP) “in bad faith”.
Keir Starmer withdrew the party whip from his predecessor in November over his suggestion that anti-Semitism in Labour had been “dramatically overstated”.
Corbyn’s remarks had been in reaction to a report by the Equality and Human Rights Commision, which found the party under his leadership had broken the law by failing to prevent “acts of harassment and discrimination” against Jewish people.
Corbyn, whose individual membership had been restored by an internal party panel, is understood to be undaunted and expects to continue his legal action in the courts despite the setback.
But party insiders believe the Islington North MP’s case has been significantly weakened by the ruling and HuffPost UK understands general secretary David Evans will seek to recover legal costs over the application.
At a hearing earlier this month, Corbyn applied for “pre-action disclosure” of several documents ahead of a potential claim against Labour.
Among the papers sought were those related to his initial suspension in October and the decision by the ruling National Executive Committee’s disputes panel to issue him with a warning.
Corbyn’s lawyers also sought notes of two meetings of senior officials at which it was alleged the party had agreed the suspension of the Labour whip would be lifted.
They suggested that notes and minutes from a meeting between Starmer, deputy leader Angela Rayner, chief of staff Morgan McSweeney, Unite’s Len McCluskey and Jon Trickett MP would reveal that a deal was being hatched to allow Corbyn back into the party.
Labour’s lawyers had argued no such notes existed and the application was a groundless “fishing” expedition.
In a ruling on Wednesday afternoon, Judge Lisa Sullivan dismissed the application and said: “Mr Corbyn has sufficient material to make a decision on the merits of his case.”
She said that the contention that Labour possessed documents which would show “third-party interference in the decision” to suspend the Labour whip from Corbyn was “speculation based on press reporting”.
The judge added: “What is sought are ‘documents related to the decision to suspend [Mr Corbyn] from the party whip’.
“It is said this includes documents sent from Dame Margaret Hodge MP and the president of the Board [of Deputies] of British Jews.
“What, if any, communication took place, whether it was in writing, what was said and whether it was taken into account are unknown.”
Corbyn supporters, including several MPs and members of the ruling NEC, accused Starmer of plunging the party into civil war after he suspended the parliamentary whip.
They claimed the decision was “a matter of double jeopardy that flies in the face of natural justice”, given that an independent NEC panel had decided to end his suspension from the party.
Corbyn may take heart from the Judge’s remark that “Mr Corbyn has sufficient material to make a decision on the merits of his case”.
A Labour Party spokesperson said: “We welcome the court’s decision.
“The Labour Party has always acted in line with our rules and procedures. We look forward to drawing a line under this matter and uniting our party ahead of a vital set of elections.
“It is regrettable that the court’s time and our members’ money was spent on this matter.”