What is an anti-assignment clause, and why does it matter?

Every contract a business relies on was made with a specific counterparty in mind, and an anti-assignment clause is how that counterparty protects its right to keep dealing with the party it chose — not whoever buys the business later. It shows up constantly in leases, supply agreements, licences and financing documents, and it is one of the more consequential clauses a buyer can overlook.

What the clause typically controls

A standard anti-assignment clause either blocks assignment entirely or makes it conditional on the counterparty’s consent, and it often extends that requirement to a “change of control” — meaning even a share sale, where the contracting entity technically stays the same, can trigger the same consent requirement if ownership changes hands. The exact wording decides whether a deal structure that seems to avoid the clause actually does.

Why the counterparty wants it

A landlord, lender or supplier extended credit, space or terms to a specific business based on that business’s track record, financial strength or reputation. Letting the contract move to an unknown buyer without any say would hand that counterparty a new relationship it never agreed to. The clause is the mechanism that preserves their choice.

What happens if it is triggered without consent

• The assignment may be treated as ineffective, leaving the buyer without the benefit of the contract it thought it was acquiring
• The counterparty may be entitled to terminate the contract outright
• The seller, and sometimes the buyer, can face a claim for breach even where the underlying business relationship continues unaffected

Why deal timelines build around it

Because triggering an anti-assignment clause without consent creates real risk, buyers and sellers typically identify the contracts affected during due diligence and build consent requests into the closing timeline. Courts generally look at the specific wording and the parties’ conduct when a dispute arises over whether a clause was triggered, so the practical answer depends heavily on the drafting, not on a general rule.