Can an Employee Take My Customer List? Texas Trade Secret Law

The short answer, expanded

An employee who leaves with a copy of your customer list has, in most cases, taken something Texas law protects. The Texas Uniform Trade Secrets Act names "a list of actual or potential customers or suppliers" as a type of information that can be a trade secret. The list has to meet two conditions, and the company that owns it has to be able to prove both.

The first condition is that you took reasonable measures to keep the list secret. The second is that the list has value because competitors do not know it and cannot readily put it together by proper means. A list that fails either test is not a trade secret, and the claim becomes a contract claim, a duty-of-loyalty claim, or nothing.

Whether the employee signed anything changes which claims exist, not whether the list can be protected. A non-disclosure agreement adds a breach of contract claim. A non-solicitation covenant adds a second route to an injunction. Without either, the trade secret claim still stands on its own.

Is a customer list a trade secret in Texas?

It can be, and the statute says so by name. Section 134A.002(6) of the Texas Civil Practice and Remedies Code lists customer and supplier lists among the forms of business information that qualify, whether the list is tangible or intangible and however it is stored.

What decides it is how the list was built and guarded. Courts look at facts like these:

• Did the list carry information beyond names: contacts, pricing, order history, renewal dates, buying preferences?
• Could a competitor rebuild it from public sources in a reasonable time, or did it take years of sales work?
• Was access limited to people who needed it, through passwords, CRM permission levels or confidentiality markings?
• Did employees sign confidentiality agreements, and did the company remind them of those duties when they left?

A spreadsheet of every roofing contractor in Dallas, copied from a public directory, is unlikely to qualify. The same spreadsheet with each contractor's negotiated discount, decision maker and renewal month is a different thing. The fuller treatment of the definition is in what counts as a trade secret in Texas.

What if the employee never signed a non-compete or NDA?

The trade secret claim does not depend on a signed agreement. The Act defines misappropriation to include acquiring a trade secret by improper means, and using or disclosing one that was learned under a duty to keep it secret. An employee who was given the list to do the job owes that duty whether or not a document says so.

What the employee may do without an agreement is compete. Texas does not stop a former employee from working for a rival, calling on customers they remember, or using the general skill they built on the job. Section 134A.003 says an injunction may not prohibit a person from using general knowledge, skill and experience acquired during employment. The line runs between what the employee knows as a professional and what the employee took as the company's property.

That line is why memory matters less than people assume. A salesperson who remembers ten key accounts is in a different position from one who exported the CRM the night before resigning. The export is evidence of improper means; the memory, standing alone, usually is not. Whether a signed non-solicitation clause adds a second claim is a separate question with its own rules.

Example

Suppose a regional HVAC distributor's top salesperson resigns on a Friday. The following Tuesday, four of her largest accounts receive quotes from a competitor that match the distributor's pricing to the dollar. The IT manager finds that on Thursday evening she emailed herself a file called "accounts-2026.xlsx" and plugged in a USB drive. She signed an offer letter but no confidentiality agreement.

The distributor has a trade secret claim under the Texas Act if it can show the file held pricing and account data it kept behind CRM permissions. It has no contract claim. It can ask for an order requiring return of the file and barring use of the pricing, but not an order keeping her from selling HVAC equipment in Dallas. The matching quotes are the evidence that turns a suspicion into a case.

What can a court order?

Three things, in rough order of urgency. First, an injunction against actual or threatened use of the list, which the Act allows under section 134A.003, including an order to return or destroy copies. Second, damages for the loss the company suffered and the gain the employee or new employer received, with exemplary damages possible for willful and malicious misappropriation. Third, in defined situations, attorney's fees.

The emergency step, a temporary restraining order followed by a temporary injunction hearing, has its own article: getting an emergency injunction to stop trade secret misuse. The remedies as a whole are set out in the Texas Uniform Trade Secrets Act, explained.

If the list relates to goods or services sold across state lines, the company may also sue under the federal Defend Trade Secrets Act, 18 U.S.C. § 1836, in federal court, and bring the Texas claim with it. That is a strategy choice rather than a right-or-wrong one.

What to preserve in the first week

The case is usually won or lost on what the company can prove about the taking. Before anyone wipes or reissues the employee's laptop, the company should keep:

• the laptop and phone, powered off and untouched, so a forensic examiner can image them;
• email, file-share and CRM access logs for the final 30 to 60 days of employment;
• the export, download and USB history the IT system recorded;
• the offer letter, handbook acknowledgment and any confidentiality or non-solicitation agreement;
• proof of the secrecy measures: access permissions, confidentiality markings, training records;
• the first signs of use: customer emails, matching quotes, a customer who mentions the call.

Reissuing the laptop to a new hire is the most common way this evidence disappears. How far an employer may go in examining devices and accounts has limits of its own, covered in investigating a departing employee's devices and accounts.

Mistakes that weaken the claim

The company's own habits are the first thing the defense examines. The weak spots repeat from case to case.

• The list sat on a shared drive every employee could open. The reasonable-measures element is hard to meet when nobody treated the list as secret.
• The company waited months while the customers drifted. Delay undercuts the imminent harm that an injunction requires.
• Someone emailed the employee accusing them of theft before the evidence was in hand. Accusations made without proof can become a defamation counterclaim.
• A letter demanded that the employee stop working for the competitor. Texas does not allow that result without an enforceable non-compete, and the overreach costs credibility at the hearing.

How long do I have to sue?

Three years. Section 16.010 of the Texas Civil Practice and Remedies Code gives a trade secret claim three years from the date the misappropriation was discovered, or should have been discovered with reasonable diligence. A misappropriation that continues over time is treated as one claim, so ongoing use does not restart the clock.

The practical deadline is far shorter. An injunction depends on showing that harm is imminent, and a court will ask why a company that knew in March waited until October. The statute governs damages; the calendar governs the injunction.

When to involve a litigator

As soon as the evidence suggests the list left with the employee. The first decisions, which devices to preserve, whether to send a letter or file first, whether to name the new employer, and whether to seek a temporary restraining order, are made in days and are hard to undo. A litigator can also say early if the list will not qualify as a trade secret, which saves the cost of a hearing that cannot be won.

Tina Wysk represents Dallas businesses in trade secret and departing-employee disputes in state and federal court. Her trade secret litigation practice covers both the company whose list was taken and the company accused of receiving it.