HathiTrust — $6,600-$13,000/yr scaled to total library expenditure; 18 years operational

HathiTrust Digital Library uses a three-tier cost model based on the member's Total Library Expenditures reported via IPEDS / CARL / CAUL. Annual fees range $6,600-$13,000 for the majority of members, split between two components: a public-domain-items component and a copyrighted-items component. Continuous operation since 2008 — eighteen years.

For C-0030: HathiTrust is the third long-running consortium that follows the proportional-fee, easy-ingestion, automated-contribution pattern. Together with CLOCKSS (E-0080, 20 years) and LOCKSS (E-0081, 27 years), it forms the empirical base for the surviving-consortium economic shape: scale-aware fees produce participation that is rational at every member institution size, which produces enough participants to fund continuous operation, which produces the multi-decade horizons these three consortia have demonstrated.