Bob Cohen wasn't even born when a previous owner of his shop allowed a property tax debt to mount from the years 1911-15.

However, he is obligated to pay.The 72-year-old man recently received a notice saying he owes $1,151 in back real estate taxes on his downtown Pittsburgh beauty and barber supply business.

The debt had gone undetected as the property changed hands several times since the 1920s, including Cohen's purchase of the busi-ness in 1983. Such debts didn't accrue interest at that time, so the amount hasn't increased.

"This is no way to treat people," said Cohen, who paid $1,134 in 1997 taxes in April.

The passage of time and ownership doesn't absolve Cohen from responsibility, said Jack Chielli, a spokesman for the Allegheny County Controller's Office.

"The law doesn't exonerate taxes upon change of ownership," Chielli said.

"That's why real estate companies do title searches," he said.

The county sold its list of delinquent tax liens to a Georgia-based collection agency, GLS Capital Services Inc., for $34.4 million last year. Most of the liens dated to the 1990s, while the oldest was from 1908.

Chielli said a title search was conducted in the 1920s but failed to alert the buyer or seller to the outstanding debt.

Now Cohen must either pay up or seek a court order to make the company that conducted the title search settle the debt.