But the AIDS hotline number is still publicized by public health groups.
When New York City's Fire Department relinquished its toll-free fire safety hotline a few years ago because of an administrative slip-up, Prime Tel grabbed it the moment it became available.
In the fall, authorities sent subpoenas to several, including Prime Tel, asking for information on how they acquire numbers and why.
And in October, federal agents and Philadelphia police spent two days removing records from National A-1's office suite, although it is unclear if the action was related to the phone business.
From the late 1980s until around 2005, teenagers who dialed the national hotline used by Teens Teaching AIDS Prevention would reach a call center in Kansas City, Mo., where other youths were waiting to answer questions about the disease.
When that program ended, the number was soon routed to one of National A-1's sex lines.
Dial the same number now and you get a recording of giggling women offering to talk dirty to you. Dial 1-800-Chicago and instead of reaching a tourism hotline for the Windy City, you will hear a woman offering "one-on-one talk with a nasty girl" for $2.99 per minute.
Records obtained by The Associated Press show that over the past 13 years, a little-known Philadelphia company called Prime Tel Communications has quietly gained control over nearly a quarter of all the 1-800 numbers in the U. and Canada, often by grabbing them the moment they are relinquished by previous users.
Others apparently respond to the come-on and supply their credit card number.
"I guess enough people go for it that it makes business sense," said Aelea Christofferson, president of ATL Communications, another company that specializes in toll-free services.
The man listed on many government records as the top executive at both Prime Tel and National A-1, Richard Cohen, declined interview requests. They wouldn't have them if they didn't need them," Helein said of Prime Tel's huge pool of numbers.
A lawyer for both companies, Charles Helein, would not discuss their business dealings in detail but said Prime Tel isn't breaking any rules or engaging in prohibited practices such as selling numbers or obtaining ones it doesn't intend to use. He said the company's large share hasn't caused any shortages: "Everybody's got all the numbers they need." Helein said the raid last fall was not aimed at Prime Tel.
There is nothing illegal about using toll-free phone services to promote adult entertainment, and callers aren't charged unless they supply their credit card information.