Lawyers for Margaret M. Donovan, a grandmother who has battled for four years to stop the conversion of her apartment at 393 Broadway St. into a condominium. Friday persuaded the state Superior Court to invalidate an order of eviction issued in 1979.

For the first time since 1977, when condominium conversion began in the building. Donovan said yesterday that she feels "relieved." The building's landlord sold Donovan's apartment, where she has lived for 23 years, to an area couple as a condominium two years ago and an cviction notice was served after she refused to leave.

Current legislation in Cambridge that restricts condominium conversion became law after Donovan's case began. David L. Sullivan, the city councilor who drafted the new laws, said yesterday the case "shows what someone would have to go through without these protective laws for tenants."

James K.H. Chin, who now own the apartment and was the other litigant in the case, "could still appeal but probably won't." Sullivan said. Chin was unavailable for comment.

A lifetime resident of Cambridge and a retired school teacher from Roberts Elementary School. Donovan said she has seen "people driven out all around" by efforts to convert rented property into condominiums.