• An agreement of the Prime Contractor, subcontractor or supplier to waive their lien rights where the agreement is in anticipation of, and in consideration for, the awarding of a contract or subcontract is against Missouri public policy and unenforceable. §429.005 R.S.Mo.
• Lien rights cannot be waived in a contract.
• A pay-if-paid clause cannot impliedly waive lien rights [§431.183 RSMo.].
• "Paid if Paid" is enforced if explicit.
• "Pay when Paid" suggests time for payment.
• Pay-when-paid and Paid if Paid clauses in the subcontract or purchase order do not create a condition precedent to payment.

Retainage Provisions

Public

• The rate of retainage is 5% of the value of the contract unless the owner and the architect or engineers determine that a higher rate of retainage is required. As of August 2014, however, the maximum rate of retainage also cannot legally exceed 5%. Changes entering into force as of August 2014 also provide that a public owner may also retain up to 10% if the contractor is not required to obtain a surety bond on the project, which is to say if the value of the project is $50,000 or less. The latest statute revision also provides that if a public owner determines that certain aspects of a public project are not substantially or satisfactorily completed, the owner must provide a written explanation within 14 calendar days to the contractor, which must then inform any subcontractor or supplier that might be held responsible. Failing to provide this notice means the public body must pay at least 98% of the retainage within 30 calendar days.

Private

• Retainage is to be held by the owner in trust for the benefit of the general contractor, subcontractors or suppliers in proportion to their interests. Retainage is capped at 10 percent unless there is a default. MO. REV. STAT. § 436.303. Contractors, subcontractors at any tier may provide substitute security in lieu of cash. MO. REV. STAT. § 436.306. There may be line-item release of retainage. MO. REV. STAT. § 436.321. Within 30 days of substantial completion, as defined, all retainage or substitute security must be released less 150 percent of the value of the punch list. MO. REV. STAT. § 436.324.