If Ryanair really want to stop Lastminute.com doing this, it doesn't take a genius to realise there are ways to adapt your booking system to make it very difficult (I avoid using the word impossible here) for any third-party to interface with you. At least they can make it very expensive for Lastminute.com by making their web systems change regularly.

The only way that Lastminute.com would be able to book flights with Ryanair is if ryanair then had a published interface that allowed agents (perhaps traditional travel agents) to book their flights. And if they do this, then why are they bitching about Lastminute.com doing this?

Why do they care if lastminute.com are booking their flights? Ryanair will still get the same amounf of cash as if the person had gone straight to them. If anything, lastminute.com will eventually lose out, as people will realise that they can direct from ryanair for cheaper surely?

Presumably they charge people to use their interface for commercial means. e.g Skyscanner.net can give cached and live Ryanair (and others) prices. Haven't seen Ryanair complaining about that or is this because Skyscanner aren't profiting from Ryanairs back?

First up, you don't really need a published legitimate interface to ride on the back of someone else's service, just some web scraping (aka screen scraping). One way to fight back would be an eBay-esque term of use that expressly forbids that kind of processing (a trick also employed by others, like XE.com's currency conversion site).

Of course you can always go ahead anyway and bounce through the Tor network to avoid detection (not that I would do such a thing) but it does make it a little more difficult for a casual scraper and of course in cases like lastminute.com they have to admit their abuse of your system in order to provide their service to their customers, so there's no real way to hide in the end.

In answer to the question I claimed to be replying to, the reason's pretty obvious and not very respectable. Ryanair want you to go to their site to buy tickets, which means you aren't going to be able to conveniently compare what they offer with others. The problem is not so much that lastminute.com sell Ryanair tickets, but that they sell non-Ryanair tickets.

Same sort of issue that some insurance or financial companies have with price comparison websites: seems like free advertising until you realise you're permanently the seventh-cheapest option and nobody uses you for anything other than a justification for buying your competitors' services.