If there is no law to the contrary in the place where personal property is situated, it is considered to follow the person of its owner and is governed by the law of the owner's domicile.
Mont. Code Ann. § 70-1-109
Choice of law as to personal property
En
Official source: Montana Code Annotated (Montana Legislature). Reproduced from public-domain Montana statutes; confirm against the official source for the current text. Not legal advice.