The due diligence phase of M&A is one of the most important parts of dealmaking: whether it’s done properly can make or break a deal. And as deal timelines stretch and data volumes swell, the nature of due diligence is evolving – from a procedural checkpoint to a strategic enabler.

So, what does success look like? And how can dealmakers get there? Sam Dormon recently sat down with in-house counsel Mary Bartle of Informa and private practitioner Anthony Doolittle of Hogan Lovells to explore the challenges and strategies for achieving success in due diligence and across the entire M&A lifecycle.

Beyond the Checklist

According to anonymized data from Datasite, the average time a deal remained on its platform increased from 6.9 months in 2021 to 10.2 months in 2024. Much of this elongation is attributed to the growing complexity and depth of the due diligence process. But what’s driving this shift?

In-house legal teams often measure procedural success by how well the process is managed: timelines met, data rooms organized, and communication flowing smoothly. But true success goes deeper. Substantive success means delivering insights that are not just accurate, but also contextualized – they should be aligned with the buyer’s commercial objectives and strategic vision.

This distinction is critical. A generic, “off-the-shelf” due diligence report may tick boxes, but it won’t help a buyer understand how a target business fits into their broader goals. That’s where tailored, insightful due diligence becomes invaluable.

For law firms, due diligence is a deliverable and a reflection of their value. High-quality due diligence should be:

• Thorough and complete, leaving no loose ends
• Delivered on time and within budget
• Infused with sector-specific expertise

But above all, it must be useful. If it doesn’t help the client make informed decisions, it has failed its purpose.

Setting scope and expectations

The early stages of a deal offer a “golden window” to define the scope of due diligence. This is the time to align on what matters most: the deal rationale, the business model, revenue streams, customer concentration, key costs, and strategic plans post-acquisition.

Buy-side teams should proactively share insights with external counsel: how the business operates, where its value lies, and what integration might look like. This context allows lawyers to focus on what truly matters, rather than chasing irrelevant risks.

Navigating hurdles

One of the biggest challenges in due diligence is the quality of information provided by the seller. Sophisticated sellers may package their business cleanly, but others may lack the experience or advisory support to do so. This can lead to mismatched expectations, especially in competitive or cross-cultural deal environments.

In such cases, creativity and resourcefulness are key. When data is sparse, a well-placed phone call, internal expertise, or even a conversation with the management team can help fill in the gaps.

Another challenge is time. Due diligence can be endless; there’s always another stone to turn over. The most effective teams know how to prioritize: identify deal-breakers, focus on key risks, and avoid getting lost in the weeds. Scope definition is not just a formality, it’s a strategic tool.

Tools, teams, and tech

To streamline the process, teams are turning to better coordination, clearer communication lines, and smarter use of technology. Properly structured data rooms, AI-powered tools for summarizing and organizing information, and collaborative checklists are transforming how due diligence is conducted.

In-person sessions, when feasible, also add value, allowing for deeper questioning and real-time insights.

Due diligence is no longer just about uncovering risks, it’s about understanding value. By aligning scope, leveraging expertise, and embracing technology, dealmakers can transform due diligence from a bottleneck into a strategic advantage.

Learn how Datasite can help you achieve success in due diligence.