What will a dispute do to the short term price of NATS shares?
Nothing... As the shares are not publicly listed. Even if they were, it's one of the quirks of share trading that sometimes a company taking on its staff over pay can increase the price due to investors seeing a 'strong management' and potentially increased dividends due to minimising increases in staff costs.
As I recall the shares are valued twice a year and the valuation based on a standard set of measures. The next-but-one valuation at the end of the calendar year could potentially see a dip if we'd had industrial action during the summer that affected revenue.
Hopefully they'll pull an acceptable offer out of the bag. I doubt it though and I really, really hope that the membership stand up to be counted. Both management AND the union exec need to be shown we can collectively act and not just whinge.