IP often sits at the center of a deal’s valuation story. In acquisitions, investments, strategic partnerships, and licensing transactions, patents, trademarks, copyrights, software, data rights, and trade secrets can look solid from a distance and much shakier up close. That gap is where expensive surprises tend to live.
A target company may say it “owns the IP,” but diligence often reveals a more complicated picture: missing assignments, stale filings, unrecorded liens, open-source issues, contractor-created code with unclear ownership, or licenses that quietly limit transfer rights. The World Intellectual Property Organization’s guidance on IP due diligence describes the process as a review of ownership, license rights, and encumbrances precisely because those details can affect deal value, structure, and risk allocation.
In this post, you’ll learn six common IP due diligence mistakes that can turn into costly deal friction, why they matter, and how buyers, investors, and founders often frame the fix. If you want a broader foundation first, this overview of how IP diligence works in practice helps set the stage.
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IP diligence problems rarely stay confined to the legal folder. They can affect purchase price, indemnities, escrow demands, disclosure schedules, financing terms, integration planning, and even whether a transaction closes on the original timeline.
That is especially true when the target’s competitive edge depends on proprietary technology, brand rights, content, data assets, or know-how. The USPTO notes that assignments and other documents affecting title can include not only transfers, but also security interests, mortgages, and liens, all of which can be relevant to ownership and control analysis in a transaction. The agency’s assignment dataset documentation also reflects how frequently these title-related records appear in the real world, with millions of recorded patent transactions and related interests on file. USPTO assignment records search and USPTO patent assignment dataset
The practical point is simple: if the deal thesis depends on IP, diligence usually extends far beyond confirming that registrations exist.
One of the most common diligence failures is relying on a company’s high-level statement that it owns its patents, software, trademarks, or content without testing the ownership chain document by document.
That approach can miss problems involving founders, former employees, consultants, acquired subsidiaries, university affiliations, joint development partners, and offshore development shops. In patent matters, the USPTO explains that parties may record assignments and other title-related documents through Assignment Center, and its search tools exist specifically to review changes in ownership and recorded interests. USPTO patent assignments Similarly, the USPTO provides recordation and search tools for trademark ownership changes. USPTO trademark assignments
In practice, the surprise often appears in one of these forms:
Cooley has written about patent ownership issues in a way that resonates with deal practice: assignment protection often depends on both the contractual framework in place before creation and the actual assignment documents executed afterward. Cooley on patent assignment and ownership
Here’s what this often means in a deal: the asset may still be fixable, but the timing gets worse. Cleanup that looks easy after signing can become leverage before closing. That can translate into reduced price, delayed funding, or special indemnity language.