• A Waiver from the original contractor to the owner cannot be presumed to waive the lien rights of lower tier contractors and materialmen.
• Most likely, lien rights can be waived in a contract before performing any work. Oklahoma law seems to be ambiguous on this subject. The question remains to be definitively answered.
• Oklahoma apparently has not answered the question whether a pay-if-paid clause possibly waives lien rights. The best practice is to assume that it will.
• "Paid if Paid" is enforced if explicit.
• "Pay when Paid" suggests time for payment.
• Pay-when-paid clause in the subcontract or purchase order does not create a condition precedent to payment.

Retainage Provisions

Public

• The rate of retainage may not exceed 5 percent of all partial payments. In a subcontract,
  the maximum rate of retainage is 5 percent. OKLA. STAT. tit. 61, § 226. A contractor may
  substitute securities in lieu of retainage. OKLA. STAT. tit. 61, § 113.2 Neither the Department of Transportation nor the Turnpike Authority may withhold retainage on public contracts. OKLA. STAT. tit. 61, § 113.1.