Police moved in late Wednesday afternoon after the protesters sat down in the Comcast Corp. lobby and linked arms. They somehow made their way inside while a larger group was demonstrating in front of the skyscraper.
The demonstrators did not resist arrest as they were cuffed and led into a police van, while supporters cheered and chanted.
The protesters in Philadelphia, like other groups around the country, had earlier called on workers and students to take part in a 99-minute "symbolic strike," asking them to leave their offices and schools to join the group starting at noon.
"I'm here to show my solidarity with Occupy Oakland and my support for Scott Olsen, a veteran who bravely served his country and was the victim of police violence in Oakland for exercising his right to free speech," said Jen Bello, who said she had walked to City Hall from her office job a few blocks away to take part in the rally.
Olsen, a former Marine, remains hospitalized with a fractured skull after he was struck in the head with a projectile at a protest in Oakland, Calif., on Oct. 25. The former Marine's plight has become a rallying cry at Occupy protests around the world.
Before the Occupy Philadelphia group marched to Comcast, several hundred chanted and carried signs as they walked with police escorts to the offices of U.S. Sen. Pat Toomey a few blocks away.
The demonstrators have marched to the Republican lawmaker's office several times since the protest began Oct. 6.
Philadelphia Police Deputy Commissioner Richard Ross said those arrested would likely be charged with trespassing. Demonstrators have been arrested one other time since Occupy Philadelphia set up its tent compound in City Hall on Oct. 6.
Bri Barton, 22, from Philadelphia, said she was at the protest because the gleaming Comcast tower represents excessive wealth in a city with many blighted neighborhoods.
"It's hard for me to see this and that existing in the same city," she said.
The arrests came the same day as Comcast said its profit rose 5 percent in the third quarter. Comcast reported its net income rose to $908 million, for the July to September period, up from $867 million the same time a year ago.