League One Leyton Orient wants a ground-share at the £429million venue.
Owner Barry Hearn said:
"The rules of the bidding process created by the London Legacy Development Corporation (LLDC) we do not believe provided for teaming, which is for all parties to share the stadium.
"It is our legal opinion that this is a fundamental flaw of the bidding process.
"We have gone to the High Court to have the decision struck out."
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