LMA—The Merck Research Labs tower on the Emmanuel College campus has lost the zoning that allowed it to be built in a residential area, Boston Redevelopment Authority (BRA) spokespeople said. The BRA is now giving it its own zoning to fix the problem.

The tower was developed under the college’s zoning, but that expired in 2010. Apparently, that also means Emmanuel currently lacks correct zoning.

No changes to the tower are expected. The 12-story research tower site is currently zoned as residential.

Merck did not have an immediate comment.

The Merck tower is part of a growing trend in the Longwood Medical Area (LMA)—the “endowment campus.” Emmanuel owns the land but has ground-leased it to Merck, which has built the tower.

A ground lease is when a company leases a plot of land for a long period of time—Merck has a 75-year lease with Emmanuel—then builds on that land. At the end of the lease, the land and the building belong to the lessor.

Merck is the current owner and user of the building, so the BRA wants to “keep track of who’s where,” said BRA Senior Project Manager Sonal Gandhi.

“This is a technical means to correct zoning,” Gandhi explained.

“It’s an opportunity to create really specific zoning,” said BRA spokesperson Melina Schuler.

According to Gandhi and Schuler, the new Merck Planned Development Area (PDA) zoning will act as an overlay to previously existing residential zoning.

A PDA is a comprehensive development plan that describes a business’s existing facilities, long-range planning goals and proposed projects. The business must update and renew its PDA periodically and must amend it whenever it adds or changes any project significantly. The PDA serves as zoning approval for all its projects.

The site and tower were part of Emmanuel College’s Institutional Master Plan (IMP) until 2010, when the IMP expired.

An IMP is similar to a PDA, but it is used for nonprofit institutions. Emmanuel is currently developing its new IMP.

Where the tower’s site will be listed is still unclear: since Merck leases the land, the BRA has not yet decided if the parcel should be included in Emmanuel’s upcoming IMP or if it should be bundled with Merck’s tower in its PDA.

Merck’s tower on the Emmanuel campus is located on the corner of Blackfan Circle and Blackfan Street. Emmanuel has set aside that corner of their campus for other ground lease projects and is calling the area their “endowment campus.”

Emmanuel’s “endowment campus” includes two other such properties—Parcel A, under negotiation to be reincorporated into Emmanuel’s academic campus; and Parcel C, the proposed site for a new tower that would belong to Brigham and Women’s Hospital. The hospital’s development will be included in its own IMP, not Emmanuel’s.

Emmanuel College is located on the Fenway between Avenue Louis Pasteur and Brookline Avenue.