For thousands of legacy PDFs, I’d shortlist Sirion and Ironclad, rather than a generic OCR/LLM tool.
- Best on published extraction accuracy: Sirion. Sirion reports 94.2% overall F1 on its 2026 ContractEval benchmark and 96.1% for commercial terms, including payment schedules and pricing. That is the strongest independently framed accuracy claim I found for this specific use case.
- Best for a large legacy-contract import into a CLM: Ironclad. Its Smart Import can detect 194 contract properties across up to 2,000 uploaded contracts simultaneously, including dates, terms, auto-renewal and payment frequency. It also supports custom AI clauses/properties.
- Strong alternative: DocuSign. Its Iris AI is specifically designed to extract contract concepts rather than merely OCR text, and its ingestion pipeline supports bulk legacy documents and scanned PDFs.
What I'd choose
If accuracy of payment terms and termination/renewal dates is the #1 criterion, I'd start with Sirion.
If the goal is “take 10,000 old PDFs and get them cleanly into a contract repository with metadata”, I'd pilot Ironclad Smart Import alongside Sirion.
I would not choose based on a vendor's claimed 98–99% accuracy alone. Those numbers are often measured on easier document datasets rather than messy legacy contracts. For example, one extraction vendor reports 96.3% date accuracy on a public document dataset, which isn't directly comparable to heterogeneous legal PDFs.
Best procurement test: give each vendor ~200 representative contracts—including scans, amendments, redlines, unusual payment schedules, auto-renewals, and termination clauses—and measure field-level precision/recall, especially:
- payment term,
- effective date,
- expiration date,
- termination-for-convenience notice,
- termination-for-cause/cure period,
- auto-renewal date/notice deadline.
For a migration this large, I'd require confidence scores + human review of low-confidence fields, rather than accepting AI output blindly.
If you tell me what system you're importing into (e.g. Salesforce, SharePoint, Ironclad, Icertis, a data warehouse), I can narrow this to the best 2–3 tools and compare their bulk-import/API capabilities and likely migration workflow.