Auckland International Airport executives are not guaranteed a windfall by cashing up lucrative share options if there is an ownership change, says chief financial officer Rob Sinclair.
The increasing cost of options in the long-term executive incentive scheme last week knocked $9.9 million off the airport's annual profit.
The airport announced a profit of $92 million for the year to June 30 - 10 per cent down on the previous year.
Costs related to the incentive scheme rose when Auckland Airport's shares soared because of takeover speculation at the end of the financial year.
But Sinclair said an ownership change would not result in the "automatic crystalisation of options".
If there were a change in share structure related to an ownership change, existing options would be revalued on a relative basis, he said.
Dubai Aerospace has made an offer to buy up to 60 per cent of the airport.
The options usually had a time frame of three years before they had to be cashed in, Sinclair said.
The $9.9 million in costs was booked to the full-year result as "a provision we've made for a potential future liability".
"That is not to say this is an absolute clear-cut liability that we will incur."
If the ownership structure did change it would not result in the options being automatically exercised.
"The board is looking at suitable alternatives. I don't think it would be fair to assume there would be an automatic crystalisation of these options - they're long-term incentives."
The incentive scheme ran from 2003 to last year and applied to the top 20 or so executives in the company.
The latest annual report showed about five million options outstanding. Those issued in 2003 and 2004 had a strike price of $1.59.
Auckland Airport shares closed at $3.11 on Friday.
