When Lyme Properties signed a multi-million dollar deal last December to redevelop Science Park, a nearby biotechnology complex, the company promised major changes that would revitalize the city’s biotech industry. But as some tenants of Science Park are finding out, those changes include forced relocation.

The first stage in the Cambridge-based Lyme’s development project is the overhaul of Building 25, located at the corner of Winchester Avenue and Munson Street. Shortly after Lyme acquired the property, David Clem, Lyme’s chief executive, notified 21 tenants who did not have long-term leases that they may have to relocate. Now, the tenant demographic of Science Park is changing, as these companies begin to leave.

In a memo to Building 25 occupants dated Dec. 18, 2000, Clem wrote, “The majority of tenants in Building 25 do not have leases. Lyme has directed Fusco Management Co. to notify all tenants of our decision to terminate tenancy at will occupancies in the building.”

Laura Woznitski, projects manager for Lyme in New Haven, said that since the winter, her company had been meeting with those tenants to establish whether they could sign long-term leases, and hence, whether they could remain.

“In preparation for renovation of the building, we had to have long-term leases with tenants,” Woznitski said. “Those with whom we were able to negotiate long-term leases, our construction is going to work around. Those that are unable to enter long-term agreements, we are not able to work around, and they were asked to leave.”

Woznitski said she then met with every tenant individually and explained Lyme’s procedure. In its first phase of a multi-year project, the development firm is beginning to completely remodel the building and overhaul all mechanical and plumbing utilities.

Woznitski did not specify the names of tenants facing eviction from the six-story, red, green and gray building. She did, however, comment on the ongoing negotiations with the Service Corps of Retired Executives, which occupies approximately 539 square-feet of space under a month-to-month lease. SCORE Chairman Jose A. Canas had been upset with Lyme’s decision to terminate SCORE’s occupancy, Woznitski said.

“I briefly spoke with Mr. Canas this morning,” Woznitski said. “He was unaware of a meeting Lyme had with two representatives from SCORE on June 20 to discuss their requirements. Jose and I agreed to meet tomorrow so that we could work out some form of agreement.”

Canas was unavailable for comment Thursday.

Woznitski said she expects construction on the building to commence in the “very near term.”

The Lyme project is one of several large investments in Science Park, which is developing from a beleaguered district to a booming locus for biotechnology. This transition remains apparent with dilapidated and abandoned red-brick buildings lying across Winchester Street from the new state-of-the-art Genaissance laboratories.

But if the building at 25 Science Park is an indicator, progress may come at the expense of other New Haven businesses.