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The Act distinguishes between suppliers who have a direct contract with the prime contractor and those who do not. They are classified as either first-tier or second-tier subcontractors. Definitions are very important under the Miller Act.
First-tier claimants, are those who provide labor or materials directly to the prime contractor and are not subject to any notice requirements. A first-tier claimant need only wait 90 days from the date on which the last of their labor was performed or materials supplied to file suit. However, suit must be filed within one year from the last date labor or material was supplied.
A second-tier subcontractor is one who has a contractual relationship with a subcontractor of the prime contractor. Second-tier claimants must give timely notice of their claim.