Independence Blue Cross wants to promote itself with a stripe of new digital signage that would wrap around three sides of a 19th and Market Street building anchored by a subsidiary of the insurer.

And its Center City neighbors are not happy.

With landlord Brandywine Realty Trust, Independence Blue Cross is proposing a  lighted sign that would run between the third- and fourth-floor windows of the building. The sign would display logos and other messages from the 1900 Market St. building's tenants, which include IBC's AmeriHealth Administrators unit, Wawa and shared-office operator WeWork.

Local residents fear that the sign would project unwanted light into the windows of neighboring buildings while detracting from Center City's historic character and mellow vibe.

"Upper-story signage casting light into people's homes does not seem consistent with the continuing residential and commercial reinvigoration of Center City," Center City Residents' Association president Charles Goodwin said in a Dec. 21 letter to City Council President Darrell Clarke, whose district includes the building. "We believe it will have an adverse environmental impact on Center City."

The plan is the latest in a recent string of proposals for outdoor signs that have attracted scorn from neighbors and other opponents.

The city's Art Commission rejected in November plans for big advertising signs on two government-owned buildings near City Hall, while neighbors in December jeered a development proposal in South Philadelphia that would include a digital billboard visible from Interstate 95.

At 1900 Market St., IBC and Brandywine are seeking community support for legislation to change provisions in the site's zoning that ban outdoor signs at the height being proposed, Goodwin said in an interview late last week. The sign would wrap around the Market, 19th and 20th Street frontages of the eight-story building, which had long been home to the Philadelphia Stock Exchange and was recently renovated by Brandywine.

Though the Center City neighbors group is opposed to the plan in its current form, it is willing to consider compromises, such as moving the sign to a lower floor or having it switched off at night, Goodwin said in his letter to Clarke, which was shared with the Inquirer.

Clarke spokeswoman Jane Roh said in an email that the Council president is working with "community stakeholders toward a resolution that respects all major interests."

Donna Crilley Farrell, IBC's vice president of corporate communications, said in a statement that her company's focus was also on ensuring that the process moves forward "appropriately and collaboratively."

Brandywine Realty Trust chief executive Jerry Sweeney said in an email that he looked  forward to coming up with a plan agreeable to all sides.

"The west Market Street corridor is in the midst of transforming from a 9-to-5 office corridor to a lifestyle mixed-use neighborhood," Sweeney said. "We believe our proposal adds vibrancy and excitement to this emerging neighborhood."