Indiana Code Title 8. Utilities and Transportation § 8-23-9-18

Sec. 18. (a) Each contract entered into under this chapter must provide for final payment within one hundred eighty (180) days after final acceptance of the contract.  However, final payment may not be made on any amount that is in dispute or the subject of a pending claim, but final payment may be made on that part of a contract or those amounts that are not in dispute or the subject of a pending claim.  Partial payment does not constitute a bar, an admission, or estoppel or have any other effect as to those payments in dispute or the subject of a pending claim.

(b) For the purpose of this section, a dispute exists when the contractor makes any claim for increase or decrease to any part of the contract or seeks additional compensation for any reason.