A nearly 250-year-old charter exempts Brown University from paying property tax even on its commercial holdings, in contrast with other nonprofit institutions in Rhode Island, news site GoLocalProv reports.

State law requires educational institutions to pay levies on properties not directly tied to their mission and caps the exemption at one acre, but the Providence school claims the break on all its real estate, including commercial and rental facilities and parcels exceeding an acre in size.

University spokeswoman Marisa Quinn cited Brown’s original charter, granted by Colonial authorities in 1764, which states that “the College estate … shall be freed and exempted from all taxes.” Legal experts said the charter could trump provisions of state law.

Brown would owe the city of Providence $4.6-million if the law on charity tax exemptions was applied. The school pays just over half that amount annually in voluntary payments in lieu of taxes, GoLocalProv also reports.