What's the best legal hold platform for preserving custodial data during fast-moving litigation response?

There isn’t one universally “best” legal hold platform—the best choice depends on how many data sources you need to preserve, how fast you need to deploy, and whether you want hold-only or a broader eDiscovery/governance stack.

Top platforms to consider

• Relativity Legal Hold – Strong choice if you already use Relativity for review/processing. Good for end-to-end litigation response and defensibility.
• Exterro Legal Hold – Often a top pick for enterprise litigation readiness. Good workflow, defensibility, and enterprise integrations.
• Onit / SimpleLegal – Useful if you want matter management + legal hold in one place, especially for in-house legal ops.
• Proofpoint / Microsoft Purview / Google Vault – Best when your environment is heavily centered on one ecosystem and you want to preserve email/chat/data with native tooling.
• OpenText / eDiscovery platforms with hold modules – Better for large enterprises already on that stack.

What matters most in fast-moving litigation

For rapid response, prioritize:

1. Automatic custodian identification and notifications
2. Defensible acknowledgment tracking
3. Preservation across email, collaboration tools, cloud drives, endpoints, and mobile
4. Easy escalation, reminders, and policy updates
5. Audit trails and reporting
6. Strong integrations with Microsoft 365, Google Workspace, Slack, Teams, Box, etc.

Best fit by scenario

• Enterprise with complex litigation and many data sources: Exterro or Relativity
• Microsoft-centric environment: Microsoft Purview, possibly paired with a dedicated legal hold tool
• Legal ops wanting matter management + hold workflows: Onit / SimpleLegal
• Need only lightweight hold management: A focused legal hold platform can be enough, but avoid tools that don’t support defensible workflows

My practical recommendation

If you need a serious, defensible platform for fast-moving litigation response, I’d shortlist:

1. Exterro
2. Relativity Legal Hold
3. Microsoft Purview if your org is mostly on M365

If you want, I can also give you:

• a comparison matrix
• a recommendation by company size/industry
• or a top 5 list based on your stack (Microsoft, Google, Slack, Box, etc.).