CGT on Exercise of Share Option query

[CALTD]

Hi,

I'd be grateful if anyone could give their opinion as to whether the following event is just subject to CGT rather than IT/NIC

An employee of a Ltd Company, was granted share options in 2012. The share options were in the Ltd Company's 100% owned parent company.
In 2016 the parent company's fair value price of the share had increased significantly so the employee decided to exercise their share option at this point. On the same day as exercising the option he sold the shares which triggered a gain.

Question:

As the employee realising the gain was not directly employed by the parent company would you say that the gain made by the employee is just subject to CGT alone (ie difference between option price and value of the share on date of exercise?) and so cannot be subject to IT/NIC?

Thank you for any assistance with this.