As we reported in mid-June, Bonhams will offer a 25-vehicle supercar collection at an auction in Switzerland on September 29. Among the cars, seized from an African “prince” found guilty of various crimes, is one of only six 2014 Koenigsegg One:1 vehicles, which the Swedish automaker calls “the world’s first mega car, producing more than one megawatt of power.”

The One:1 reportedly has been driven only 597 kilometers and Bonhams announced a pre-auction estimated value of €1.6 million to €2 million ($1.8 million to $2.25 million).

But in a very unusual move, Koenigsegg has publicly objected to that estimate.

“Bonhams has put an estimate for the car that is way under market value,” the automaker says on its website.

“For some reason, not understood by us, Bonhams are uninterested in giving a correct starting point or accurate estimate for the One:1, as they have shown complete lack of interest in trustworthy facts and figures presented to them. At the same time, they are unwilling to substantiate their estimate to us with any facts or findings whatsoever.

“We at Koenigsegg are not willing to stand by on the sidelines and observe this wrongful and harming behavior without reacting.

“In order to give Bonhams a base for a relevant estimate, we have gone out of our way to provide them with all the actual selling prices for the One:1 model known to date. Factual prices that are in some cases more than twice their top-end estimate. None of the prices known are even close to as low as Bonhams’s estimate. The trend shows that values are only increasing.

“Furthermore, Bonhams told us there was a possibility to buy the car pre-auction. Given their initial reluctance to adjust their estimate, we submitted offers substantially higher than that.

“Not only did they decline the offers, they did not even use these relatively low firm offers as reason to correct their estimate to that level. In our view this further shows a total lack of interest in providing transparency to the market and is unfair to the seller and the car.”

All of the cars at the auction, being conducted in behalf of the State of Geneva and its state auctioneer, are being offered with no reserve.

Nonetheless, Koenigsegg continues its argument: “The prime asset of Bonhams is their credibility. Given this, we are bewildered as to why they are totally uninterested in using trustworthy market information as basis for their upcoming auction and instead they choose to stick with numbers that are totally unfounded. Bonhams are simply not doing their job or living up to their reputation as a serious auctioneer.

“Our most recent models, the Regera and Jesko, both sold out in record time. Our older models are all appreciating in value alongside the growth of our company. The star among these models – the limited edition One:1 model, of which only 6 examples were produced (plus a prototype) – have all enjoyed hefty value increases, when sold, contrary to Bonhams’s estimate that indicates a hefty price drop.

“This is not about the auction itself,” Koenigsegg continued. “Given the above, we are confident the car will catch a good value there. We know there are buyers, including ourselves, who will seek to put their hands on this car.

“The question is, why should bidders, who trust Bonhams’s judgment, not be given a fair chance to jump on the opportunity, instead of stopping their bids short, based on information Bonhams knows is incorrect?

“In effort to provide Bonhams all the opportunities to do the right thing, we sent them a draft of this text in advance so they can correct their estimate. They did revise their estimate slightly to a figure ($2.3 million) that is still not even close to proven market value and substantially lower than our firm offers.

“Given the above, we were unfortunately forced to share our findings and have to conclude that you cannot trust ‘appraisals’ coming from Bonhams.