Every programmatic impression travels a path from publisher to advertiser. That path determines how much of your bid actually reaches the auction, how many middlemen take a cut, and whether you're buying from a legitimate source or a reseller three hops removed from the original inventory.
Supply Path Optimization is the practice of analyzing and cleaning up those paths so your media dollars work harder.
The Problem: Not All Paths Are Equal
When you bid on inventory through a DSP like DV360, The Trade Desk, or Amazon DSP, your bid doesn't go directly to the publisher. It travels through one or more SSPs, exchanges, and sometimes resellers before reaching the auction.
Each hop in that chain typically means:
- Fees — SSPs and intermediaries take a percentage
- Latency — More hops means slower auction response
- Opacity — Harder to verify where your ad actually runs
- Duplication — The same impression sold through multiple paths, bidding against yourself
A single publisher might be available through 5, 10, or even 20 different supply paths. Some are direct relationships with low fees. Others are third-party resellers adding markup without adding value.
If you're not actively managing this, you're overpaying.
What SPO Actually Means in Practice
Supply Path Optimization isn't a single tactic. It's a discipline that includes:
1. Path Analysis Understanding which SSPs and sellers are offering you inventory from a given publisher. Are they authorized direct sellers? Authorized resellers? Or something murkier?
2. Allowlist Curation Building and maintaining lists of verified domains and apps where you want your ads to run — and ensuring those paths go direct when possible.
3. Fee Transparency Knowing the take rate at each step so you can calculate true working media and compare paths objectively.
4. Seller Verification Confirming that the sellers offering inventory are actually authorized by the publisher. If a seller isn't authorized, you're taking unnecessary risk.
5. Bid Efficiency When you remove wasteful paths, your effective bid in the remaining auctions is higher. Same budget, better win rates, cleaner inventory.
Why This Matters Now
Programmatic has matured, but the supply chain hasn't cleaned itself up. Header bidding created more paths, not fewer. Resellers still proliferate. And most buyers don't have time to manually audit every domain on their allowlist against every SSP's seller declarations.
Meanwhile, the pressure on working media ratios keeps increasing. Clients want to know where their money goes. Procurement teams want receipts.
SPO is how you answer those questions with data instead of guesswork.
Where Alargo Fits
We built Alargo to make supply path verification fast and practical.
Upload an allowlist or connect your DSP, and Alargo analyzes every domain to show you which sellers are authorized, which paths go direct, and where you're exposed to reseller hops.
The goal is simple: help you buy cleaner inventory, reduce wasted spend, and win more auctions at better prices.
No more spreadsheets. No more guessing. Just verified supply paths before you activate.
Ready to see your supply paths clearly? Start free at alargo.ai