LEWISTON – Bates Mill No. 3, the long brick building at the center of the 10-acre Bates Mill Complex, has been sold.

Mill 3 Development Co., a spinoff of Platz Associates, which developed and renovated the 1863 building, sold it on July 20 to Twin Cities LLC, a Maine-based company managed by local developer William H. Johnson. The 160,000-square-foot building is totally occupied by TD Banknorth, which also occupies the adjacent Storehouse No. 7 at the mill complex.

“The only change for us is the rent check goes to a different address,” said Jeff Nathanson, spokesman for the bank, which employs about 1,000 people locally. “From the perspective of a tenant, the sale has zero impact.”

The bank’s lease on the property extends to at least 2015, which transfers to the new owner. Twin Cities’ purchase price was not disclosed.

Formerly Peoples Heritage Bank, the bank centralized its back-office processing operations at the mill complex, beginning with its occupancy of Storehouse No. 7 in 1997. The commitment provided an anchor tenant for the 1-million-square-foot complex, which was jointly developed by Platz, its partners and the city after the previous owner abandoned the complex in 1992.

The city owns the undeveloped Mill No. 5, which has been touted as a potential convention center, as well as a boiler plant. Platz’s Bates Mill LLC owns the other buildings and has been systematically renovating and leasing each.

“This is the first we’ve sold,” said Stephan Myers, development director for Platz. “It was never our intent to buy, fix and sell, but an offer was made.”

The most recent renovations were completed at Storehouse and Wing No. 2 (the new home of DaVinci’s restaurant) and are ready for tenant fit-up, said Myers. Next on the schedule is Mill No. 2 (former site of Floor Systems).

“The plan is to keep going here, as we have,” he said.