An energy company granted permission to dump waste ash from Didcot Power Station in a lake failed in an attempt to remove campaigners from its land.
Pumping of waste into Thrupp Lake starts later this year
The homeless group recently occupied Sandles, a house belonging to the firm RWE npower, which adjoins Thrupp Lake, in Radley, Oxfordshire.
RWE npower's application for an eviction order was thrown out of Oxford County Court on Wednesday.
Save Radley Lakes, a separate group, were present outside the court.
RWE npower was told it would not be granted an eviction order because not enough time had passed between the serving of notice and the court date.
The firm will apply for a new order to be served on Thursday and said it hoped to go back to court next week.
Marjorie White, of Save Radley Lakes, said: "We are not condoning illegal activity, but to have this group come out and support us has just been heartening."
RWE npower said plans to dispose of non-recyclable waste from the power station in the lake were given the final go-ahead on Monday.
Work on a long-term restoration plan for the area, devised by the company, will begin once the lake has been filled.