Spend EfficiencyGoogle AdsProgrammatic

Account-Level Exclusions + Principal Media: How to Stop Wasted Spend in Opaque Inventory

UUnknown

2026-02-16

10 min read

Pair Google’s Jan 2026 account-level exclusions with principal media transparency checks to cut wasted spend and boost ROAS.

Stop Wasted Spend Now: Pair Google’s Account-Level Exclusions with Principal Media Checks

Hook: If your campaigns eat budget on low-quality inventory—even under automated formats like Performance Max—you’re not alone. Wasted spend from opaque supply chains and mixed-quality placements is one of the top reasons ROAS stalls in 2026. The good news: pairing Google Ads’ new account-level placement exclusions with disciplined principal media transparency checks creates a practical, repeatable way to eliminate that waste.

Executive summary (most important first)

Google rolled out account-level placement exclusions in January 2026, letting advertisers block unwanted inventory across Performance Max, Demand Gen, YouTube and Display from one central setting. At the same time, Forrester and industry reports confirm that principal media—reselling/representing inventory with incomplete transparency—is here to stay. To stop wasted spend you must: (1) centralize your exclusion rules in Google Ads, and (2) run a principal media transparency playbook to ensure those exclusions target real sellers and not just surface-level placements. This article gives a step-by-step workflow, real KPIs, and templates you can implement this week.

Why this matters in 2026

By early 2026, the landscape shifted decisively. Google increased automation across formats (Performance Max, Demand Gen), and also added controls—like account-level exclusions—to give advertisers guardrails without killing automation. Meanwhile, principal media practices expanded across programmatic channels as publishers and intermediaries sought scale, per Forrester’s January 2026 report. That combination makes two realities unavoidable:

Automation can compound waste fast if bad placements slip through at scale.
Account-level controls are necessary but not sufficient—because opaque supply chains can mask the true seller.

The core idea (one sentence)

Use Google’s account-level exclusions as the control plane, and use principal media transparency checks as the verification plane. Together they cut low-quality spend, improve efficiency, and preserve the benefits of automation.

Step-by-step playbook: From audit to ongoing governance

1) Run an immediate low-quality inventory audit (48–72 hours)

Objective: find where wasted spend is occurring—domains, apps, YouTube channels, and programmatic sellers. Focus on recent 30–90 day windows across Performance Max, Demand Gen, Display, and YouTube.

Pull placement reports in Google Ads for last 30/60/90 days (Campaign > Placements). Export domains/apps and match against spend, impressions, conversions, and CPA.
Cross-reference with GA4/BigQuery engagement signals: session duration (engaged sessions), bounce rates, conversion rate by placement. Example filters: placements with CTR < 0.05% AND session duration < 10s AND conversion rate < 25% of account average.
Flag placements with unusually high invalid traffic or low viewability (viewability < 20%).

Quick metric thresholds (start here, adjust to your business):

CTR < 0.03% on display/video AND bounce > 80%
Viewability < 20%
Conversion rate < 25% of account baseline for non-brand traffic
CPA > 150% of target AND spend > $500 last 30 days (to avoid noise)

2) Build the first account-level exclusion list (72 hours)

Objective: Stop the highest-impact waste immediately using Google Ads’ account-level exclusions.

Create a new Account-level exclusion list in Google Ads (Tools > Shared library > Placement exclusions).
Populate with the top 50–200 placements flagged in the audit (prioritize by spend × poor KPI impact).
Apply the exclusion list across Performance Max, Demand Gen, YouTube and Display campaigns.

Tip: Start conservative—exclude placements with the clearest red flags first. Because exclusions apply account-wide, use a staged rollout to avoid accidentally blocking experimental or partner placements.

3) Run principal media transparency checks (3–14 days)

Objective: Verify that the placements you exclude are controlled by the true supply-side entity and identify opaque resellers that require deeper action.

What is principal media in practice? It’s when an entity buys inventory from a publisher or another reseller and then presents that inventory under its own umbrella or domain—often without full supply-path disclosure. That makes it hard to know whether exclusions or blocklists actually reach the endpoint inventory.

Principal media transparency checklist

Request seller.json and ads.txt/ads.cert data for flagged domains/apps.
Ask programmatic partners (including your DSP) for a Supply Path Optimization (SPO) report showing the chain of sellers for high-spend placements.
Request the exact seller/display domain that won the auction—ask for auction-level metadata for suspicious spend buckets (consider tooling and telemetry reviews like the Oracles CLI review for auction-level logs).
Validate impression provenance: compare the domain reported in Google Ads placement reports vs. seller.json ownership. Look for mismatches or masked domains.
Flag intermediary-owned domains (resellers) that route multiples publishers into one opaque bucket—these are principal media candidates.

Action: If your exclusion targets a reseller domain, ask the partner to show the publisher-level mapping and instruct them to apply your exclusion at the publisher endpoint. If they can’t, escalate to your procurement or account rep—do not assume the block worked.

4) Close the loop: block at the source and log evidence (1–2 weeks)

Objective: Ensure exclusions take effect and prevent reappearance via resellers.

For each excluded placement that originates from a principal media reseller, request proof that the reseller applied the exclusion at the publisher endpoint.
Where possible, block the publisher's root domain as well as any known reseller domains in the account-level exclusion list.
Keep a change log (spreadsheet or ticketing system) recording the date of exclusion, who applied it, and the audit evidence — consider a public or internal doc approach (see Compose.page vs Notion for public docs).

5) Implement ongoing governances and automation (30–90 days)

Objective: Turn the manual audit into a scalable program so you don’t re-learn the same lessons each quarter.

Automate weekly placement reports and flagging rules (use Google Ads scripts, Looker Studio, or BigQuery to create alerts for placements exceeding your thresholds).
Set a monthly principal media verification cadence with programmatic partners (SPO reports + seller.json verification).
Include account-level exclusion maintenance in your campaign changes SOP: every time you launch a new format, ensure the exclusion list is reviewed.
Define escalation paths—if a partner refuses to disclose sellers or apply exclusions at the source, pause spend with that partner until compliance is confirmed.

Practical templates you can copy this week

Account-level exclusion quick-start template

Use this ordered approach to build your first list:

High spend & worst KPI placements: top 50 by spend where CPA > 150% and engagement < thresholds.
Known malicious/brand unsafe domains (from your brand safety provider).
App bundles and misattributed apps (packaged apps with low sessions).
YouTube channels with high impressions but low view-time and high bounce.
Opaque reseller domains identified in principal media checks.

Principal media transparency request email (copy/paste)

Hi [Partner],

We're conducting a transparency audit for placements in account [Account ID]. Please provide the following for the attached list of placements: (1) seller.json data, (2) auction-level seller/domain for impressions in the past 90 days, and (3) confirmation you've applied our account-level exclusion to the publisher endpoint. If you cannot provide these, please advise how you plan to remediate within 7 business days.

Thanks, [Your Name]

How to measure success (KPIs and expected impact)

Baseline measurement is critical. Track these KPIs before and after implementing the controls:

Wasted spend reduction (spend on flagged placements / total spend).
Overall CPA and ROAS by campaign type (Performance Max, Demand Gen, Display, YouTube).
Viewability and invalid traffic rates.
Conversion rate and revenue per thousand impressions (RPM) for non-brand traffic.

Realistic outcomes based on recent audits and pilots in late 2025–early 2026:

Immediate reduction in low-quality placement spend: 15–30% within 30–60 days for mid-size accounts.
Improved ROAS: 10–25% uplift when wasted impressions are eliminated and budget reallocated to high-performing placements.
Lower invalid traffic percentage and better viewability—leading to higher conversion efficiency over time.

Case example (anonymized): In a 2025 audit of a mid-market ecommerce advertiser, we identified $45k/month routed through two principal media resellers that reported inflated impressions from bundled apps. After applying an account-level exclusion list and forcing publisher-level blocks, wasted spend dropped 22% in 60 days and ROAS improved 18% as budget shifted into verified placements.

Advanced checks: supply path, seller provenance, and measurement integrity

For programmatic-heavy accounts, basic placement blocks aren’t enough. Use these advanced techniques:

Supply Path Optimization (SPO): Request SPO reports from your DSP and map which SSPs and resellers are passing inventory. Favor direct publisher paths or SSPs with verified seller.json records — see tools and telemetry reviews such as the Oracles CLI review for auction-level workflows.
Seller provenance matching: Compare the domain in your placement report to seller.json ownership and the ads.txt/ads.cert entry. Mismatches indicate masked or resold inventory.
Auction-level reconciliation: Ask for auction-level logs (impression ID, winning bidder, seller domain). Reconcile with your own impression-level telemetry where possible — consider edge datastore strategies for cost-aware querying of high-cardinality telemetry (edge datastore strategies).
Measurement robustness: Use both Google Analytics 4 and server-side measurement to ensure conversion counting isn’t distorted by spoofed or falsified impressions. For storage and measurement durability, evaluate edge and server-side storage tradeoffs (edge storage tradeoffs).

Common pushbacks — and how to respond

“Exclusions hurt automation and performance.” Response: staged exclusions and conservative thresholds preserve automation while removing the worst placements. Measure performance impact and revert changes only with data backing it.
“The reseller says exclusions were applied—trust them.” Response: require proof—show the publisher mapping or auction-level confirmation. If they can’t provide it, keep the block and escalate.
“We don’t want to block too much inventory.” Response: prioritize blocks by spend and impact. Use temporary 14–30 day exclusions and monitor the replacement spend patterns.

2026 trends to plan for (short-term and strategic)

Keep these trends top of mind when building your 2026 ad operations roadmap:

Platform guardrails will increase. Expect more account-level controls from major ad platforms—use them but verify with provenance checks.
Principal media will persist. Forrester’s early-2026 guidance is clear: the practice is entrenched, so institutionalize transparency checks with suppliers.
Privacy-first measurement and server-side telemetry will become standard—invest in measurement hygiene to detect spoofed impressions and verify conversions. Consider distributed and server-side storage reviews when building telemetry pipelines (distributed file system reviews).
Budget-level controls (like Google’s total campaign budgets) mean you can be bolder with exclusions—Google can optimize spend within set budgets, so prioritizing quality pays off.

Checklist: What to do in the first 30 days

Run a 30–90 day placement audit and identify top low-quality placements.
Create and apply an account-level exclusion list for the top offenders.
Send principal media transparency requests to DSPs/partners and gather seller.json/SPO evidence.
Block at the publisher endpoint for any reseller-mediated placements (document proof).
Set up weekly alerts and a monthly governance review to keep the exclusion list fresh.

Final recommendations — practical governance you can keep

Account-level exclusions are a powerful lever. But without principal media verification they can be cosmetic. Implement a two-track program: centralize exclusions in Google Ads as the immediate control, and run principal media transparency checks to ensure those exclusions reach the true supply sources.

Follow a measured cadence: immediate audit and exclusion (30–60 days), principal media verification and source blocking (60–90 days), then automation and governance (ongoing). Use the templates and checklist above to get started this week.

Call to action

Want a fast way to quantify wasted spend and get a prioritized account-level exclusion list? We can run a 7–day inventory audit and principal media check for your account and deliver a prioritized exclusion pack plus a supply-path verification report. Click to schedule a technical audit and stop wasting budget on opaque inventory.

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