WHEN Singapore bosses call in computer forensics experts, there is usually one thing they want: their former employees' deleted e-mail.

Employers suspect that some departing staff try to hide wrongdoings by deleting incriminating e-mail before they leave, while other workers often e-mail to themselves information they want to take with them.

But the cyber trail can be uncovered even if a computer has been burnt or thrown into muddy water. And any data put on thumbdrives or external hard drives can also be traced.

Anything done in a computer is traceable, said computer forensics experts, but not many people know this and the complacency can land them in hot water.

Last week, seven former Citibank employees faced 1,223 charges under the Computer Misuse Act of taking clients' information before leaving to join rival UBS.

The private bankers, who handled accounts of wealthy clients, allegedly sent the data to their personal e-mail addresses. Some also printed out information.

This is not the first time former employees have been taken to court for allegedly 'stealing' data.

In 2001, two lawyers set to leave the high-profile law firm Lee & Lee copied over 2,000 confidential files from its database for later use. They were both fined $5,000.

And it is not just confidential computer data that is off-limits to departing staff.

Lawyers say that all documents, letters, e-mail and even name cards generated during the course of employment belong to the company and cannot be taken when an employee leaves.

Taking company property may seem harmless but it is stealing, said Mr David Leong, managing director of recruitment firm People Worldwide Consulting.

Mr Leong said: 'It is like taking a wallet from a table or walking into an unattended hotel room to steal.'

A former employee is also obliged not to disclose or use the trade secrets of his old company, said lawyer Toh Kok Seng, a partner at Lee & Lee.

Trade secrets, such as a list of the employer's clients, is the sort of information that is not freely available in the marketplace, he said. A journalist's list of contacts would also fall into this category.

Leaks of trade secrets can cause huge financial losses. Citibank allegedly lost about $50 million of business to UBS when its private bankers jumped ship and took their clients with them.

The issue of leaving a firm and taking along client information is less clear in the legal and health sectors.

Clients here tend to associate themselves with the professional rather than with the company, which is why they tend to move when their lawyer or doctor moves.

These exceptions aside, 'data is a key commodity', said Ms Ferhana Omar Ashiblie, general manager of CBL Data Recovery Technologies, a computer forensics firm. 'Some of this information is priceless, and could contain decades of research or records.'

Employers do not take chances when it comes to protecting their intellectual property, especially in cut-throat industries such as banking or insurance.

United Overseas Bank employees with access to high-level or sensitive information may be put on garden leave if they resign. This means the employee stays at home on full pay but is prevented from joining a rival firm until his notice has been served.

OCBC Bank staff sign a secrecy declaration form on Day 1, agreeing to preserve customer information.

The 24-hour quit notice is also widely applied, especially if an employee has been hired by a rival, said Mr David Ang, president of the Singapore Human Resources Institute.

But lawyer Chou Sean Yu, a partner at Wong Partnership, thinks there is only so much employers and technology can do.

Mr Chou said: 'There are security measures which companies can adopt but if an employee is intent on stealing information, there's no stopping him.'