James P. Gillespie, a member of the Citizens to Save the Warner Theater, said earlier this month that he was trying to put together financing to buy the building, which had fallen into disrepair since being placed on the National Register of Historic Places in 1979.
Gillespie could not be reached for comment yesterday.
Greenberg said that when no serious offers to buy the building materialized, he continued with plans to demolish the structure built by Warner Bros. in the 1930s.
The West Chester Borough Council granted Greenberg a demolition permit in June after months of delays.
The council had denied Greenberg's request for a permit in February on the recommendation of the borough's Board of Historical Review. Greenberg filed an appeal in Common Pleas Court in March but delayed the court action while he waited for an offer from Gillespie.
In the meantime, the borough solicitor, Stephen McGuire, told the council there was no legal ground to deny the permit, and the permit was granted.
"I'm always sorry to see any of the older building in town go, especially one that has had the impact of the Warner," said W. Barry Wright, borough council president. "It served as a place of entertainment for many years. There was a noble fight put up to save it. Unfortunately, it wasn't a winning fight."
Greenberg said that Port Contractors of Wilmington would demolish the theater at a cost of $150,000. He said the job would take about four weeks.