The oldest move in procurement is telling one supplier what another one bid. Most buyers have made it. We have made it. It feels like the shortest route to a lower price, and on the day it often works.
We think it is the most expensive habit in the job. It caps the price you get. It teaches every supplier in the category to pad. And it slowly empties your next tender. We built a product that refuses to do it, and this post explains why.
What the incumbent hears
The numbers below are invented, but you will recognize the shape. A packaging contract worth $3.2M a year goes out to tender. The incumbent bids $3.2M again. A challenger comes in at $2.9M, about 9% lower. The category manager calls the incumbent and says, "You're about 9% above the other bid."
Two weeks later the incumbent comes back at $2.89M. The team books $310k of savings and keeps a supplier it knows. Everyone is pleased.
Now look at what the incumbent learned on that call. It learned the exact number it had to beat. So it beat it by ten thousand dollars and stopped. Its real floor might have been $2.7M. Nobody will ever find out, because the buyer told it where to stop.
Its account team also wrote the number down. Next year's renewal conversation starts from $2.9M, and the incumbent already knows what your market looks like from the inside.
We call this the price relay. A relayed price sets a ceiling on your savings. The supplier who hears it has no reason to go a dollar past it.
What the other bidder learns
The challenger spent three weeks on that bid. Site visits, a costed model, a pricing committee. It lost to its own number, quoted back by someone else.
Suppliers work this out fast. Account managers move between competitors in the same industry, and they talk. Once a supplier suspects its price was shown around, it bids with you differently. Its first number becomes an opening position. Or it stops bidding altogether, because it has worked out that its job in your process is to be a price check.
Then the next tender gets two responses where it used to get five. Both are padded. Your benchmark for the category now rests on numbers built to be relayed.
Show one supplier another's price and you win one round. You pay for it in every round after.
The soft versions leak too
Few buyers read the other bid out loud. They hint. "You'd need to sharpen your pencil by high single digits." "You're not in the top two on freight." "The other side came in under three."
Each of those is a relay with the decimals taken off. An account manager hears "high single digits," does the arithmetic, and lands a point under it. A pricing desk hears "under three" and comes back at $2.99M. The hint carries almost everything the number would have.
Buyers usually do this with good intentions, often late in a quarter with a savings target to hit. We understand the pressure. The supplier still walks away knowing where to stop.
Governments put it in writing
Public procurement got here before most companies did. The US Federal Acquisition Regulation, at section 15.306(e), bars contracting staff from revealing an offeror's price without that offeror's permission.
The same paragraph spells out what a contracting officer may do. They can tell a bidder its price looks too high, or too low. They can show the analysis behind that view. They can tell every bidder what price the government's own research found reasonable.
The rule takes away the other supplier's number and leaves the buyer's own case intact. We read it as commercial sense as much as ethics. A buyer known to leak bids stops getting honest ones.
Most private buyers work under no such rule. We think every procurement team should adopt it anyway.
Argue from your own number
So what moves a supplier, once the other bid is off the table? Your own case. A should-cost model for the packaging, built from board and resin prices. What you paid last year, and what those inputs did since. The line items where this bid sits above anything you have seen.
A supplier can always dispute a number it cannot see. A model it can check is harder to wave away. Say "your corrugated line is 14% above what board prices support," and the conversation turns to board prices. Say "the other bid is lower," and it turns to whether you are bluffing.
Three changes cover most of it. Put a line in your RFP saying bids stay sealed and no supplier will see another's price, then keep to it. Build a should-cost or a price history for every category you take to market, so you walk in with a number of your own. And when you need a supplier to move, tell it the price is high and show it why, the way a contracting officer would.
Some rounds will close slower. We think the trade is worth it every time.
A rule we wrote into the product
Whispor keeps a short list of things it never does. Telling one supplier another supplier's price is on it, next to signing a contract and going outside a limit you set. In Sourcing, every response stays sealed until the deadline. After it, each finalist is negotiated one to one, and no supplier is shown another's price, during the event or after it. Autonomous Negotiation trades between your target and your limit, one term against another, without quoting anyone else's bid.
A supplier that trusts its bid stays sealed sends you a real price the first time. We would rather build for that supplier than for the one round you win by leaking.
The Whispor team
Related: Why suppliers anchor high (and what actually moves them) · Benchmarks tell you what other teams settled for. · Best and final is neither.