Walker Morris / News & Insights / How can you protect your business interests, client contacts and confidential data when a key employee leaves?
Walker Morris / News & Insights / How can you protect your business interests, client contacts and confidential data when a key employee leaves?
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How can you protect your business interests, client contacts and confidential data when a key employee leaves?
1st December 2025
“When a key employee is planning to leave, you’ll need to make sure that your business interests, customer contacts and confidential information are protected. To do so, it’s essential to make sure you know what post-termination restrictions are in place and how they prevent an employee from causing damage to the business after they depart. You’ll also need to know how those restrictions can be enforced if necessary.
In this article, we explore the most common post-termination restrictions, how you can enforce them and what evidence you need for successful enforcement.”
What restrictions apply?
First, check what post-termination restrictions the employee is bound by. You’ll typically find these in their employment contract.
The most common restrictions are:
The restrictions should be time-limited and applied to relevant geographical areas. A confidentiality clause can apply for so long as the information concerned remains confidential.
Are the restrictions enforceable?
Just because there is a restriction in an employee’s contract, this doesn’t necessarily mean it’s enforceable.
To be enforceable, a restriction has to protect a legitimate business interest and go no further than is reasonably necessary to do so.
Each matter has to be considered on a case-by-case basis. There is no one size fits all approach, as what is reasonable for one employee, may not be reasonable for another.
There are also some common faults to be aware of. For example:
What evidence do you have?
Evidence is key in showing whether the former employee is in breach of their restriction after they’ve left.
There are a number of places you may be able to obtain evidence:
However, caution needs to be taken to not conduct excessive evidence gathering, particularly if the employee is still employed by the business and hasn’t yet left (i.e. if they’re on gardening leave). You want to avoid the employee concerned arguing that you breached the employer’s duty of mutual trust and good faith, which could impact upon the enforceability of the restrictions.
We think there’s a breach, what can we do?
If you suspect there’s a breach and you have evidence to support that, then acting quickly is in the best interest of the business.
The first step in doing so is preparing a comprehensive Letter Before Action and requesting undertakings from the employee.
If the employee has a new employer, a Letter Before Action can also be sent to them to put them on notice that to the extent they induce any of the employee’s breaches they may also be pursued. You can also request undertakings from the new employer to that effect.
If that doesn’t resolve the situation and there is a serious risk of damage to the business, then you will want to consider obtaining an urgent interim injunction to prevent further damage. This is an order from the court that a party refrain from doing something, until a final trial.
How we can support you?
If you need support with enforcing post-termination restrictions, preparing a Letter Before Action or obtaining an urgent interim injunction, contact Jack Heward.
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Heward
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Heward
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Heward
Director
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jack.heward@walkermorris.co.uk
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Heward
Director
Dispute Resolution
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