What actually happens when a page loads an advert: who is involved, where the money goes, and why site owners ended up with so little control over it.
Internet advertising is described, from the outside, as though it were a single transaction: an advertiser pays, a reader sees an ad, a publisher gets money. Inside, it is a chain of separate businesses, each performing one step and taking a share for performing it. Understanding the chain is the fastest way to understand why publishers so often feel that they have no control over what appears on their own pages, and why the amount that reaches them bears so little relation to what the advertiser spent.
A visitor opens a page. The page contains a tag — a piece of script the publisher pasted in. The tag reports that an impression is available, along with whatever it can determine about the visitor. That request reaches an exchange, which offers the impression to bidders. Bidders decide, in milliseconds, what this particular impression is worth to them. The winner's creative is returned and drawn into the slot.
Every participant in that sequence is a company with costs and a margin. None of them is unnecessary in a system designed to sell one impression at a time to whoever wants it most. But the publisher chose only the first one, and the price is determined at the fourth.
The advertiser's payment is divided among the intermediaries before the remainder reaches the site. Publishers are usually told the net figure — what arrived — rather than the gross, which makes the deductions difficult to examine even when they are legitimate. This is not a conspiracy; it is what a long supply chain does. Each hop is a real service. The trouble is that the person who owns the audience is at the end of the queue, not the front.
To decide what an impression is worth, the system needs to know something about the person seeing it. That is done by storing an identifier in the visitor's browser and building a profile against it across sites. UK PECR and the EU ePrivacy Directive both require consent before anything is stored on, or read from, someone's device — which is precisely why sites carrying conventional advertising need a consent window before the ads can work properly.
An ad that is sold by the day to a named advertiser does not need to know who is looking at it. Perch's embed stores nothing and reads nothing: no identifier, no profile, no third party. Serving it to UK or EU visitors adds no consent requirement at all. If your site is banner-free today, it stays that way — which is worth stating precisely, because it is a claim about the embed, not a verdict on your whole site. Your analytics and any other third-party scripts are what decide whether you need a banner.
Once inventory is sold impression by impression to an anonymous market, three things follow automatically. You cannot know in advance which advertisers will appear on your page. You cannot know what a day will pay. And you cannot promise an advertiser anything about placement, because you are not the one making the placement decision.
Site owners accepted this because the alternative — finding advertisers yourself, agreeing a price, chasing an invoice — was more work than most sites could justify. That trade was reasonable when the only way to sell space directly was by telephone. It is much less reasonable when the buyer is already reading the page.
Selling space directly reverses each of those three losses. You know the advertiser, because you approved them. You know the rate, because you set it. You know where the ad sits, because you pasted the tag there. The chain has one link in it, and the fee taken from each payment is stated up front rather than deduced from a statement.
The honest limit is fill. An exchange will always find somebody to occupy an impression; a direct space is empty until a specific person decides to buy it. Perch narrows that gap by making the empty slot itself the sales pitch — an unsold space carries a visible invitation to advertise, so the reader who runs a business can buy it in about two minutes — but a small site should expect days when nothing is sold, and should price accordingly rather than assume constant occupancy.
If you are weighing it up, how to choose between online ads platforms sets out the questions to ask of any of them, and the help centre covers the mechanics of setting a space up. If you want the short version: the fewer parties between the money and the page, the more of both you keep hold of.
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