Marc Andreesen (@pmarca on Twitter) has been toying with a theory of public company shareholder. The short (Twitter) version is "At any given time, public co's shareholder base consists entirely of one of: growth investors, value investors, arbitrageurs, or nobody." This has been refined through tweets.

The growth investors will hold a stock as long as the rate of revenue growth does not slow. When it slows they dump - and the shares of really fine companies can fall sharply because the growth rate falls from (say) high single digit to mid single digit. What are objectively great results can see 25 percent price falls simply because the results do not measure up to the expectations of the shareholder base.

The growth investors don't much care about earnings (they come later). But they do care how big the eventual market becomes.

A recent example of a fall (which may or may not be justified) is Amazon who were seen missing lofty expectations for Christmas sales. [The sales numbers were fantastic, just the expectations were more fantastic.]

A fallen growth stock doesn't become fashionable again until it has a lower-than-market price-earnings ratio where it attracts "value investors".  Value investors have a different agenda. They want the business run for cash and maybe for buybacks. Shareholders will pressure management to meet their expectations. [Example: Apple.] If earnings fall or buy-backs slow these shareholders are disappointed.

Below the value investors - and mentioned in later tweets - are the Ben Graham style bottom feeders who get really interested when the stock is trading at half cash. Whereas traditional value investors want the business run for cash the true bottom feeders want the business closed for cash. Zynga at bottom was borderline of interest these investors.

Outside this are the arbitrageurs that just want to rent the stock for a short term deal. No deal and they are disappointed.

This is a generalization. But being a non-conformist at heart I want to look at the places between - stocks dumped by growth investors for example before they become interesting to value investors - or stocks that are approaching Ben Graham levels but still have viable businesses.

Between the cracks are interesting places to look. Zynga was interesting at the edge of being a Ben Graham stock. Google's had a slowdown that lasted one quarter. Buying a growth stock when the slowdown is temporary and lasts one quarter provides great opportunities. See January 2012 where Google dropped a double-digit percentage in a sharply rising market.*

So I am going to look at a twixt-and-between stock: Blue Nile. This is a failed growth stock that doesn't yet have a low PE and has an enormous short interest. The company recently missed and guided revenue and earnings down - which is problematic for a stock with a 50 PE ratio.

The knock on the stock: it has been missing expectations for years.

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The Jeweller with one of the all-time-great business models

Blue Nile has possibly the most seductive business model I have ever seen. It is an online build-your-own seller of engagement rings.

The modal purchaser of an engagement ring is a man in their 20s or the 30s who doesn't give two hoots about jewellery. The purchase is large (a month's salary?) and is full of terms that he doesn't know (VS2 clarity anyone). He is buying it for someone who he hopes will accept his proposal.

The ideal customer provides no return business. Ever.

The total absence of return business means that the downside for ripping customers off is low. [They are not coming back so if you gouge them it won't matter.] The high-ticket price and the general ignorance of the customer guarantees a rip-off. If the customer is at all sophisticated about human nature they know it.

The shop-keepers know this too. They have glamorous premises (which just adds to the feeling of being ripped off). They use lighting tricks to make the diamonds sparkle. And the sales guys are - in my one-off experience** - a less explicitly testosterone laden version of car salesmen. Slick. Dishonourable. But smooth, so smooth.

Into this comes Blue Nile who offer diamond engagement rings on a build-your-own basis with transparent pricing. You go to their site and choose one stone, three stone, this clasp, that clasp, this quality and size of diamond etc. They tell you if you are choosing a quality of diamond so high you can't tell the imperfections except with a microscope. As you move the slider up choosing a bigger diamond or a higher quality diamond the price changes and you can see the price change so you know how much you are paying for size/quality and settings.

The margin is thin - so there is no way you can feel "ripped off" and it comes in a blue-box which to my (admittedly unsophisticated eye) is just a darker, richer shade of blue vis the expensive boxes sold by Tiffany's.

If you have not played with the jewellery site do so. This is internet shopping at its finest.

It is also a truly great business model. Transparent pricing makes a guy keen to shop there. But the real joy is the negative working capital.

A traditional jeweller sits huge amounts of inventory around waiting for a victim (ahem: customer) to come through the door. They need to sell at a price high enough to get a return on all that inventory. Zale Corporation has $900 million in inventory. That inventory is the majority of their assets and represents about a year of cost of goods sold. The first 10% of margin is just getting a return of 10% on the inventory holding. Tiffany is even worse with $2.4 billion in inventory and annual cost of goods sold of $1.7 billion. They have 17 months inventory sitting around glistening under expensive lights and more expensive security. Margins need to be enormous just to give a return on inventory holdings.

By contrast Blue Nile recognizes diamonds are commodities and doesn't bother with all that inventory. They just buy-to-order. If you want a round-cut three-quarter carrot diamond with an ideal-grade cut and VS2 clarity it will cost you about two and a half grand and one is pretty well like another. So Blue Nile take your money, build the ring to order and ship it to you. Turn-around is not fast but is adequate and Blue Nile operate with negative working capital. At the last (and disappointing) numbers Blue Nile has $34 million of inventory (mostly non-engage ring product) and $134 million in accounts payable. The offset is a cash balance well over $100 million.

And Blue Nile can sell much cheaper than a traditional jeweller. A traditional jeweller with this turnover would carry maybe $350 million more inventory and would require a return on that. They would also need security and insurance for that inventory and would pass that onto customers. On top of that there are no premises and slick dishonourable sales people to pay. All this would add up to more than 20 percent cost advantage. The advantage that Blue Nile has over its competitors is much bigger than the advantage that (say) Amazon has over Best Buy.

If you had that advantage the rational thing to do is to price really keenly, be as honest and transparent as possible and grow and grow and grow some more. In other words to do what Amazon does. One day - sometime in the dim-distant future - growth will slow because you have captured the market and then you price with say a 8% margin and mint money.

The maths will look like this. We don't know what the "end-sustainable sales" are but for every dollar of sales there is 8c of margin. Post tax there will be about 5.6 cents of earnings. Put that on 13 times and the stock will settle out at 72 percent of sales. If end sales are a billion the market cap will be $720 million. If they are 5 billion the market cap will be $3.6 billion.

This maths gives you the quick way of valuing Amazon. Amazon sales are currently $75 billion. If they quadruple between now and maturation the end sales will be $300 billion. The end market cap will be $210 billion. The current market cap is $165 billion. If Amazon can quadruple sales the stock will be a winner. I think it probably will. But to do really well on the stock sales probably need to rise 600 percent. [We have no position in the stock.]

Alas Blue Nile is not Amazon. Despite what looks like a massive advantage and a near perfect business model Blue Nile just has not grown that fast.

In 2008 Amazon sales were $20 billion. They are now $75 billion. Sales have better-than tripled.

By contrast Nile has disappointed. Sales are only up about 50 percent. And in that time margins have slid so earnings are flat. Earnings are flat at Amazon too but nobody gives a toss. All they care about is the sales growth.

But they do give a toss at Blue Nile. Blue Nile guided for earnings/margins and missed. And their sales growth has slid to low-teens. It raises the question: if they really have a better business model why isn't it growing at the torrid pace that Amazon is growing.

One problem is that marriage just isn't that fashionable. Marriage rates are in historic decline... also people are stinging on engagement rings... but that doesn't quite explain it. Blue Nile remains way too small a part of the market.

The obvious suggestion is that engagement rings are such an emotional purchase that the bride-to-be really wants to see it and hence shops traditionally. And despite the movies men don't often get down on a bended knee and offer a surprise proposal ring-in-box proffered up ready for rejection. [I would have been way too insecure...]

And so the end market for Blue Nile is just not that big.

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But there are offsets. Blue Nile does have a reputation for not ripping you off. I can imagine plenty of Chinese want loose diamonds as a form of portable wealth. The end-market here could be enormous. If Blue Nile can capture any of that the sales will be huge albeit at low margins.

And there are some technologies out there which will make Blue Nile a very much better business. The Oculus Rift is one of the hottest venture capital concepts. Cheap highly realistic 3-D virtual reality headsets are coming. 3-D scanners will also be under $100***. When you inspect real-estate online you will be able to walk in your headset through the house in realistic, high-resolution 3-D. When you buy jewellery online you will be able to see how it looks on your (or your bride's) hand. And you will be able to tweak it so you know when that stone really is so large it is grotesque. In other words online shopping will be a much better experience.

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The value proposition in Blue Nile stock

Trailing sales are $450 million. The market cap is $442 million. Sales are growing still but the rate is disappointing. The PE ratio is over 40 but that is because the business is not earning much margin.

It is not a value stock yet. The PE is way too high.

Rather the stock is held by disappointed growth investors. After all this was the perfect business and it didn't perform.

Also it is closer to 1.0 times sales than my magical-end point of 0.7 times sales. It will get to 0.7 times sales one day - either by the price declining further or the sales increasing. Given the low-teens growth rate getting there via growth seems likely to me albeit at a slow-grind for shareholders.

In other words Blue Nile is twixt-and-between. Its not a great growth stock and is hardly a value stock.

It wouldn't be much interest to me except that it has a short interest of 20 percent of the float, is more than 115 percent owned by institutions and is - on the metrics above only about 20 percent overpriced. After all it will wind up as a value stock one day at 0.7 times sales.

We are in a market where lots and lots of stuff is more than 20 percent overpriced. So I don't get it. Can someone please explain the short interest? Do the shorts really believe this deserves to trade at half sales?

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Why we own it?

When stocks have a very high short interest and the shorts are wrong the stocks are unbelievably large winners. Think Tesla, Netflix and - dare I say it Herbalife.

So far on Blue Nile the shorts have not been wrong. This is a company which is disappointing on growth and disappointing on margins. But as I noted there are things that can go right.

Top of my list is the Chinese developing a fascination with loose diamonds. The amounts of money here are enormous - and as a general rule I don't want to be short Chinese corruption. Chinese corruption is a very big market.

Maybe more certain: the Silicon Valley guys are completely obsessed about the Oculus Rift and immersive and cheap 3-D experiences. They are early (which is their job). Still I don't want to be short a real 3-D stock. Cheap 3-D technology will change the online shopping experience dramatically. I can see Blue Nile sales eventually quadrupling - in which case the stock is very cheap indeed. But that eventual sales growth relies on technologies that will not be widespread this year and are not part of Blue Nile's publicly stated plans.

John

*I remember well. We were long. January 2012 was our worst ever month.
** I am married to my first wife. Shopping for an engagement ring really was and will remain a one-off experience.
***Lidars with the processing power in your phone and the cloud.