That's not quite what this is.

The 'best price guarantee' guarantees the customer will receive the lowest price for their ticket. Google will refund them if anyone gets a lower price.

The airline can release, for 30 seconds only, a much lower price. Then Google has to refund all their customers, and the airline might only sell a handful of tickets at the lower price.

Remember airline tickets aren't fungible. They have names attached, and can't be resold, so nobody can buy up thousands of tickets in a price dip and resell.

This seems like something you could easily cover in the terms of service. Remember that law doesn't really work like programming does.

30 seconds seem to be at least somewhat covered by their ToS.

"Prices are measured between the purchase date and the departure date of your eligible itinerary." [1]

The key things to interpret there are "between" and "departure date". For example, I would interpret that as price changes on the day of the flight don't count. (i.e between is exclusive and date means the date, not date and time).

[1] https://travel.google.com/intl/ALL_us/booking/flights/guaran...

Then google would buy all those tickets at the reduced value and resell them at the normal price.

Tickets are generally non-transferable and cheap ones are non-refundable. So unless google can predict the name of the future buyer it’ll be out of luck.

I think they have deals with carriers to bulk buy tickets without giving a name. Carrier gets cash upfront (most are desperate for cash). Google gets to play marketmaker.

The airlines really are shooting themselves in the foot though... Google will end up with the biggest slice of the pie...

Except it might be 30 seconds before the plane departs...