RSS feels like a museum piece. It is not. It is the plumbing under podcast advertising, news ingestion and a chunk of the competitive monitoring your team does every week.
A detailed explainer from PPC Land walks through what an RSS feed actually is, where the money touches it, and why browser-level changes landing in November 2026 have publishers nervous. Here is the marketer’s version.
What a feed actually is
An RSS feed is an XML file listing a site’s newest items. Each entry carries a title, a link, a date and usually a summary or full text. Subscriber software polls the file on a schedule, compares it to the last copy and surfaces what changed.
The key point for marketers: nothing sits in the middle. No algorithm ranks it, throttles it or personalises it. The publisher decides what appears, the subscriber’s app decides when to fetch. In an era where every other distribution channel is mediated, that is the whole value proposition.
The format dates to Netscape’s RSS 0.90, published 15 March 1999 and authored by Ramanathan Guha. Dan Libby’s 0.91 followed that July. UserLand shipped RSS 2.0 on 19 August 2002, copyright later passed to Harvard’s Berkman Klein Center, and the last revision, version 2.0.11, landed on 30 March 2009. The spec has been frozen ever since.
Why podcast ad dollars live inside one XML tag
The commercially important element is enclosure – a single empty tag added by UserLand in RSS 0.92 on 25 December 2000. It points at a media file with three attributes: url, length in bytes and MIME type.
That URL is where the money is. Measurement firms run prefix redirects: the publisher prepends a third-party domain so every download passes through that server first. Server logs, not client-side pixels, are the record of delivery. Dynamic ad insertion works at the same chokepoint, stitching a different spot into the file on each request.
Which means the format dictates what can be counted and sold in a channel with no cookies and no device IDs.
The measurement details that change your CPM math
IAB Tech Lab released version 2.3 of its Podcast Technical Measurement Guidelines on 21 July 2026 – a 32-page draft, with comments closing 19 August 2026. Version 3.0, aimed at streaming video podcasts, is scheduled for 2027. Things worth knowing before your next podcast buy:
- The draft extends download and ad-delivery rules to video episodes travelling through open feeds, and documents the prefix redirect method in section 5.2.
- It swaps “listener” for “podcast consumer”.
- Byte thresholds are asymmetric: an embedded ad in the first quarter counts as delivered at 25% of the file served, while a dynamically inserted spot needs the full ad to transfer.
- Three separate measurement window types are defined – identical server logs can produce three different totals.
- Episodes streamed inside Netflix never touch an open feed, so they sit outside the 2.3 framework entirely.
Add Podtrac’s finding that YouTube podcast playlist episodes retain 64% of counted views as engaged views, and you have a channel where “reach” means three different things depending on where it was served. Ask your podcast partners which window and which platform their numbers came from.
The XSLT problem
On 20 August 2025 Google engineer Mason Freed proposed removing XSLT from browsers via WHATWG. XSLT is the transformation language that renders raw feed XML as a readable page. Google cited memory-safety vulnerabilities in libxslt and usage below 0.02% of page loads. Mozilla and WebKit signalled support.
Developers catalogued breakage across the US Congress, the National Weather Service, the European Parliament, plus Australian and Canadian agencies. Chrome’s origin trial opened 25 August 2026; removal from stable hits 17 November 2026, with escape hatches expiring 17 August 2027.
Feeds themselves keep working – only the browser-rendered pretty view breaks. But if you publish a feed with a stylesheet, check it before November.
What to do about it
Three practical moves. First, if you run content, keep a clean feed live – it is the one route no platform ranks. Second, pull competitor blogs, newsletters and release notes into a reader for zero-cost market intelligence; Inoreader added AI podcast transcripts in September 2025, and Openvibe added feed support in August 2025 alongside Mastodon, Bluesky and Threads. Third, do not confuse an RSS feed with a Merchant Center product feed – same word, unrelated job.
Source: PPC Land
