Microsoft Advertising on October 28, 2026 began letting advertisers give its AI up to 40 written guidelines on what generated ad copy should and should not say, in an open pilot announced alongside general availability of its Conversions API and new search term reporting for Performance Max campaigns.

The changes arrived in a single monthly roundup on the Microsoft Advertising blog, titled "Build, steer, and measure your campaigns with AI: What's new in Microsoft Advertising this October." The post carries no byline. It also added age and gender targeting and auction insights to Performance Max, opened a pilot for audience exclusions, and introduced an AI-assisted setup flow that builds a first Performance Max campaign from a new advertiser's website and documents. A report that maps search terms to the landing pages users reached starts rolling out in mid-November. Several items are pilots that require a request to an account team, and one, device targeting, is promised only "in the coming weeks."

In Short

Microsoft, which sells the ads on Bing, Copilot and Outlook, updated its ad tools so that businesses can tell its AI what their ads should and should not say, and can see more of what their automated campaigns are doing. It also opened up a way for companies to send sales and sign-up data straight from their own systems to Microsoft, instead of relying only on code in the visitor's web browser. For advertisers, this means more control over automated campaigns that used to hide much of how they worked, though several of the features are still tests.

Four changes, one premise

Microsoft framed the roundup around a single condition. "Leaning into AI only pays off when you can steer it and see what's working," the post states. The month's updates, it says, "help you launch, tailor, and measure results of your campaigns faster with control."

The four headline items, in Microsoft's order, are:

  • AI-powered campaign creation, a new setup flow for a first Performance Max campaign
  • More Performance Max reporting, targeting and exclusions, some generally available, some in pilot
  • Messaging guidelines for AI-generated ad copy, in open pilot
  • Conversions API, now generally available

The release status of each piece matters. Age and gender targeting, search term reporting and auction insights reporting are described as available now. Audience exclusions and messaging guidelines are in open pilot. Brand exclusion changes are still being refined. Device targeting and search term landing page reporting are scheduled rollouts, the first "in the coming weeks" and the second "starting mid-November."

Building a first campaign from a website and brand documents

The first item targets advertisers who have not used Microsoft Advertising before. With AI-powered campaign creation, according to Microsoft, an advertiser can "go from sign-up to launching your first Performance Max campaign in just minutes."

The inputs go beyond a website address. Microsoft says advertisers can share "materials such as marketing plans, brand guidelines, and product images" alongside their site. The system turns that material into what the company calls "an editable snapshot of your business," covering the products or services offered and "how your ads should look and sound." The advertiser reviews and edits that snapshot, which then shapes how the AI builds the campaign. From there the campaign can be launched directly, or the budget, bid strategy, ad copy and creative assets can be changed first.

Microsoft positions the flow against the busy holiday period. "Starting on a new advertising platform can feel complex," the post says, adding that people can be reached "as they search, work, and play across Copilot, Bing Search, Outlook, and more." It closes the section with a claim that the post does not substantiate: "Your campaign will be set up to perform from day one."

Microsoft refers advertisers to a Help Center article for details. The post itself does not say which markets or languages the flow supports, what file formats or sizes it accepts, or how long the process takes in practice beyond "minutes."

The choice of campaign type is notable. By routing new accounts straight into Performance Max, the setup flow puts first-time advertisers into Microsoft's most automated format, in which a single campaign buys across search, audience and other placements and the system decides where budget goes. Microsoft launched Performance Max globally in March 2024, describing it at the time as an all-in-one product, with brand exclusions, search insights reports and search themes promised for later.

Performance Max: what is available now, and what is not

The second section of the post deals with controls that experienced advertisers have asked for. "We're continually listening to your feedback on the additional controls and reporting transparency you're looking for," Microsoft writes, before listing "what's recently rolled out and what's coming soon."

Targeting

Age and gender targeting is now generally available on Performance Max. Advertisers can include or exclude specific age groups and genders from ad delivery. Microsoft does not list the age brackets in the post.

Device targeting, which lets advertisers include or exclude specific types of devices, is "rolling out to all advertisers in the coming weeks." No date is given.

Google took a narrower step in the same direction more than 18 months earlier. Its Performance Max campaigns began receiving age exclusions in April 2025, with ranges from 18-24 to 65+ and a separate category for unknown ages. That control excludes ages. Microsoft's version, as described, works in both directions for age and adds gender.

Exclusions

Two exclusion features are in pilot. Audience exclusions, which keep specified audiences out of a Performance Max campaign, are in open pilot.

The second is a change to brand exclusions. "We're refining brand exclusions so you can choose to apply them to text ads only, while still showing up for these brand searches on product ads," the post says. In practice, an advertiser could stop text ads from appearing on searches for a given brand while keeping its product ads eligible for those same queries - a split that matters for retailers selling third-party brands, who may not want to bid on a brand name in text ads but still want their listings shown. Microsoft has offered brand lists in Performance Max since July 2024, when up to 20 lists could be created and new brand requests went through an editorial review that typically took four to six weeks.

For both exclusion pilots, Microsoft asks interested advertisers to contact their account team or Support. The post does not describe eligibility criteria.

Reporting

The reporting changes close gaps Microsoft acknowledged earlier in the year. Search term reporting and auction insights reporting for Performance Max "are now available," according to the post, so that advertisers can see "which specific searches your ads show on and how you compare with competitors."

When Microsoft added conversions, clicks and spend to the Performance Max placement report on May 7, 2026, it described auction insights as coming soon and search term reporting as rolling out within weeks. The October post links back to that May announcement on the Microsoft Advertising blog. It does not say when either report actually became available between May and October.

A search terms report lists the queries that triggered ads, which in an automated campaign is often the only view an advertiser has of where budget went on search. Google announced full search terms reporting for Performance Max on April 30, 2025, alongside channel-level performance data and asset-level metrics.

A third report is next. Search term landing page reporting begins rolling out "starting mid-November," according to Microsoft. It shows "how user intent maps to the web page they were routed to." That matters in Performance Max because the system can send users to pages other than those an advertiser specified, so the pairing of query and destination is otherwise hidden.

Messaging guidelines: 40 lines of instruction for the AI

The third item gives advertisers a written brief for generated copy. "AI can write strong ad copy in seconds, but it still needs to sound like your brand," the post says. Messaging guidelines are available in open pilot for Performance Max campaigns and for Search campaigns that have AI Max enabled.

The limit is 40 guidelines. Microsoft recommends using them "primarily" for "broader rules around claims, themes, concepts, tone, or language to avoid." Its example is a high-end retailer adding "Never imply that products are low cost." According to the company, "This helps reduce the risk of AI generating messaging that doesn't meet your brand or business requirements."

The guidelines can also be positive. Advertisers can supply "preferred wording, themes, or tone of voice." Microsoft says setting them upfront "helps maintain brand consistency and reduces the time spent reviewing and editing generated copy." The guidelines are set in the campaign creation flow, according to the post.

The wording is careful. Microsoft says the guidelines reduce risk and steer output; it does not say generated copy will always comply. The post gives no figures on how often generated copy breaks a guideline, and no detail on what happens when two guidelines conflict.

The cap of 40 is the same number Google uses. Google's text guidelines for AI Max and Performance Max combine up to 25 term exclusions with up to 40 natural-language messaging restrictions per campaign. Google introduced them as a beta on September 10, 2025 and took the beta global on February 26, 2026. Before this pilot, Microsoft's controls on generated text covered term exclusions but not messaging restrictions. Microsoft's version as described differs in one respect: it accepts positive guidance on wording and tone, not only restrictions.

The timing follows the spread of AI Max on Microsoft's platform. Microsoft began rolling AI Max out to all accounts worldwide on August 19, 2026, bundling search term matching, text customization and final URL expansion under one toggle. Weeks earlier, it had said Predictive Matching was moving into AI Max's search term matching. In September, Microsoft said that AI Max testers gained at least 8% more conversions, based on a lower confidence bound drawn from advertiser A/B tests. Text customization is the AI Max setting that generates ad copy. Google requires that setting to be switched on before its text guidelines can be used; Microsoft's post does not say whether the same condition applies to messaging guidelines in Search campaigns.

Conversions API leaves pilot

The fourth item is the most significant for measurement. Microsoft says it is "introducing Conversions API (CAPI) for Microsoft Advertising, now generally available."

"Every step so far, from setup to steering, runs on one thing: strong conversion signals," the post says. Those signals, according to Microsoft, are "the foundation for accurate measurement, AI-powered bidding, and better-performing AI campaigns."

A Conversions API sends conversion events from an advertiser's own systems to an ad platform, rather than relying on a script in the visitor's browser. Microsoft's version, the post says, connects "website, apps, CRM, and point-of-sale systems" to Microsoft Advertising "in real time through a server-to-server connection."

From per-account approval to general availability

Until now, access was restricted. In September, PPC Land reported that Microsoft had placed its Conversions API behind per-account pilot approval: advertisers could not switch it on themselves and had to ask an account manager or Support to enroll their customer ID. At that point the documented integrations were Commanders Act, Freshpaint, Invoca, MetaRouter, Segment, Stape.io and Tealium, with Adobe Real-Time CDP and Switch Growth listed as coming soon.

The October list is longer. Microsoft names three setup routes: direct integration, Google Tag Manager, or technology partners. The partners named are Adobe Real-Time CDP, Commanders Act, Freshpaint, Invoca, MetaRouter, Segment by Twilio, Stape.io, Switch Growth, Tealium and Zeotap. Compared with the pilot documentation, Adobe Real-Time CDP and Switch Growth have moved from "coming soon" to the main list, and Zeotap appears for the first time.

Microsoft's developer guide has not fully caught up. The version on Microsoft Learn, updated on October 29, still labels Freshpaint as early access and Adobe Real-Time CDP and Switch Growth as coming soon, a day after the blog post presented all three as available partners.

How the integration works

The developer guide, linked from the post, sets out the mechanics. Events go to an endpoint on capi.uet.microsoft.com, addressed by the advertiser's UET tag ID and authenticated with a bearer token that is generated through the Campaign Management API for that tag. Up to 1,000 events can be sent in a single batch.

Each event needs an event type, an event time and a block of user data. That block must contain at least one identifier from a list of seven: an anonymous ID, an external ID, an email address, a phone number, the Microsoft click ID (MSCLKID), or the mobile advertising IDs IDFA and GAID. Event times must fall within the last 90 days, according to the guide. When PPC Land reviewed the documentation in September, timestamps older than seven days were rejected.

Double counting is handled by deduplication. Advertisers running both the browser tag and the API are told to send the same stable deduplication value in the eventId field and keep event names compatible across both systems, so that one purchase is not counted twice. A consent field, adStorageConsent, takes the value G for granted or D for denied.

What Microsoft says it does

The post lists three benefits. Richer signals, Microsoft says, help "AI-powered bidding prioritize high-value audiences." More complete data gives "a clearer view of Microsoft Advertising's impact across customer touchpoints." And "Server-to-server sharing maintains persistent conversion signals while giving you more control over data sharing."

Microsoft positions the API as a complement to its browser tag, not a replacement. The Conversions API "works alongside your Universal Event Tracking tag," the post says, "capturing activity that may be missed due to browser limitations." Universal Event Tracking, or UET, is the JavaScript tag Microsoft has long used for conversion tracking and remarketing lists.

The phrase "browser limitations" carries specific weight this year. Testing of the Safari 27 beta, reported by PPC Land in July, found that Safari blocked requests to bat.bing.com, the domain that serves UET, by blocking a Microsoft ad-infrastructure IP range. Apple has not given a release date for the stable version, which was expected in the fall with iOS 27 and macOS 27. A server-side connection from an advertiser's own systems does not depend on that request reaching Microsoft from the browser.

The post names four goals the data can serve: "higher-quality leads, in-store sales, app engagement, or re-engaging shoppers with dynamic remarketing." Point-of-sale and CRM sources are what make the first two measurable at all, since neither event happens on a web page.

Google Tag Manager is a familiar route for Microsoft. In 2022, Microsoft rolled out an automated Google Tag Manager integration that copied an advertiser's existing Google tag setup to create UET tags, including product ID and page type for dynamic remarketing.

What the post does not say

The roundup leaves several questions open. It gives no availability by market or language for any feature. It provides no performance figures for AI-powered campaign creation, messaging guidelines or the Conversions API, and no measured outcome for the claim that a new campaign "will be set up to perform from day one."

It does not say whether existing advertisers can use the new campaign creation flow, or only new sign-ups. It does not set an end date for the audience exclusion or messaging guideline pilots. It does not say when the search term and auction insights reports went live in Performance Max, or whether the reports cover all queries or only those above a threshold. For the Conversions API, the post itself does not address consent, data retention or how duplicate events from UET and the API are reconciled, leaving those questions to the developer guide.

Microsoft closes by saying more updates are "coming next month" and invites feedback through its feedback portal, in-product feedback, X, Instagram or Support.

Why this matters for advertisers

The roundup arrived on the same day Microsoft reported quarterly results. Revenue from its Search and advertising line rose 10% to $6.55bn in the three months to September 30, according to its earnings release, the first quarter in which that line includes LinkedIn's advertising and Premium subscription businesses. Microsoft therefore no longer publishes a growth figure for Bing search advertising on its own. The last quarter reported on the old basis, to June 30, showed search advertising revenue excluding traffic acquisition costs up 10%, down from 12% in the previous quarter, with guidance for mid-single-digit growth in the quarter that followed. A setup flow built for advertisers who have never used the platform is one way to widen the base of a business whose growth had been slowing.

The pattern across the four items is consistent: automation first, controls afterwards. Performance Max launched on Microsoft in March 2024 with exclusions and search insights described as future features; search term reporting and auction insights were described as available in October 2026. Microsoft removed Max CPC from new non-portfolio campaigns on October 1, 2026, moving more bidding to automated strategies. Each step toward automation increases the platform's reliance on the conversion data advertisers send it - which is precisely the argument Microsoft makes for the Conversions API.

Much of the package also follows controls Google added to its own Performance Max and AI Max campaigns first, in most cases more than a year earlier. For advertisers running campaigns on both platforms, the gap between the two sets of controls is narrowing, although pilots and rollouts without dates mean it is not yet closed.

Microsoft has been adding Performance Max controls steadily through 2026. In January it doubled search themes to 50 per campaign and added a customer acquisition goal. In June it changed UTM auto-tagging so Performance Max traffic would be labelled separately from Search in analytics, effective September 2. An Ad Preview Hub across MSN, Bing Search and Outlook followed in July, and in August Microsoft let advertisers block ads next to up to 1,000 page title terms, covering Performance Max among other campaign types.

The open question is how much of the October package reaches advertisers as described. Device targeting has no date, search term landing page reporting starts in mid-November, audience exclusions and messaging guidelines are pilots, and the brand exclusion change is still being refined. Only the campaign creation flow, the Conversions API, age and gender targeting and the two new reports are presented as finished.

Timeline

Summary

Who: Microsoft Advertising, in an unsigned post on its blog. The changes affect advertisers running Performance Max and AI Max Search campaigns on Microsoft's network, which includes Bing, Copilot, Outlook and MSN, new advertisers signing up to the platform, and the ten technology partners named for the Conversions API.

What: Messaging guidelines, up to 40 per campaign, entered open pilot for Performance Max and AI Max Search campaigns. The Conversions API became generally available after a per-account pilot. Performance Max gained age and gender targeting, search term reporting and auction insights reporting, with device targeting promised in the coming weeks and audience exclusions in open pilot. Microsoft also introduced AI-powered campaign creation for a first Performance Max campaign and said brand exclusions are being refined to apply to text ads only.

When: Microsoft published the post on October 28, 2026. Search term landing page reporting starts rolling out in mid-November 2026. No dates are given for device targeting, the end of the pilots or the brand exclusion change.

Where: The post does not restrict any feature to particular markets or languages. Ads built with these tools run across Microsoft's network, including Copilot, Bing Search and Outlook.

Why: Microsoft argues that AI-driven campaigns only pay off when advertisers can steer them and see results, and that bidding and measurement depend on conversion signals. Several of the controls close gaps with Google's Performance Max and AI Max, and the Conversions API gives advertisers a route for conversion data that does not depend on a browser tag that Safari's beta has been found to block.