4 M.R.S. §253: Jurisdiction in court where proceedings originate

Subject to Title 18‑C, sections 1‑303 and 3‑201, and except as otherwise provided in Title 18‑C, section 5‑105, when a case is originally within the jurisdiction of the probate court in 2 or more counties, the one that first commences proceedings therein retains the same exclusively throughout. The jurisdiction assumed in any case, except in cases of fraud, so far as it depends on the residence of any person or the locality or amount of property, may not be contested in any proceeding whatever, except on an appeal or removal from the probate court in the original case or when the want of jurisdiction appears on the same record.