Capital Gains Tax and employee share schemes - Stocks held in the USA

In 2001 shares were bought, via ESPP scheme, on my behalf by my employer who were a UK subsidiary of a US company. My employer placed the shares in Etrade account where I sign a WBEN document periodically. I understood this to be a like a employee share scheme and were sheltered from tax in the US and UK. They are worth $18000. I want to either transfer the shares or sell them and transfer the proceeds. Question: Was my understanding correct, can the shares be transferred to the UK free of tax or is subject to UK taxation?

Hi,
It depends on the type of share scheme and how long they were held. Please refer to guidance at:
Tax and Employee Share Schemes
​​​​​​​Thank you