523G.7  Negotiable instruments.
  An invention developer shall not take a negotiable instrument from a customer as part of a contract, unless the negotiable instrument is a check constituting evidence of the customer’s obligation. A person in possession of a negotiable instrument is not a holder in due course as defined in section 554.3302, if the person takes a negotiable instrument from a customer in violation of this section.
92 Acts, ch 1114, §8