Indiana Code Title 36. Local Government § 36-12-2-3

Sec. 3. (a) The corporate boundaries of the public library must be described in the resolution of establishment, conversion, transfer, or merger filed:

(b) If the corporate boundaries of a unit and a Class 1 public library are coextensive, territory annexed by the unit becomes part of the library district if the annexed territory is not already part of another library district.  Whenever a public library annexes territory under this subsection, the library board shall file a statement describing the annexed territory:

If the territory annexed by a unit is already a part of another library district, the territory remains a part of the other library district unless the library boards of both public libraries pass a resolution of transfer under section 4 of this chapter.