A fourth lawsuit was filed yesterday to stop demolition of the Sears, Roebuck & Co. building on Admiral Wilson Boulevard in Camden, PA.

The suit was filed in Camden County Superior Court by Standard Merchandise Co. and Mark Tarnoff Associates, a business on Wright Avenue within blocks of the proposed demolition site. Campbell Soup Co., which still has headquarters in Camden, has proposed razing the historic building to make way for expansion into a new office building. Campbell plans also call for building a commercial office complex that would be visible just off Admiral Wilson Boulevard.

Campbell officials have said they would consider leaving Camden if the Sears demolition is not approved. In May the Dr. Denim firm, a national retail-clothing chain, sued Gateway L.L.C. in state chancery court to force the current owner of the building to sell to Dr. Denim. Later in May, the Historic Preservation Commission voted unanimously against razing the building. A lawsuit filed by activist Frank Fulbrook complained that the city planning board's approval was invalid. Following that suit, the state Historic Site Council voted 5-1 against demolition. Dr. Denim later filed a legal challenge to the validity of a city planning board vote for demolition.

Standard Merchandise and Tarnoff Associates, a clothing manufacturer, alleged in the suit yesterday that the planning board's resolution of support for demolition was inadequate and deficient in facts and conclusions to approve demolition