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MSFT Stock Glitch?

Tuesday, March 30, 1999 by Dave Winer.

Financial news Permalink to Financial news

Lots of financial news yesterday. Computer Associates buys Platinum for $3.5 billion. Microsoft reorganizes. The Dow closes over 10000 for the first time in history.

And late yesterday afternoon, a friend who reads DaveNet called and pointed out something interesting about the Microsoft two-for-one stock split that happened on Friday after the markets closed. With this split, MSFT crossed a threshold, for the first time, the number of outstanding shares no longer fits into a 4-byte number. This opened the possibility for computer error, similar to the Y2K problem that many people are justifiably concerned about.

The 4B Glitch? Permalink to The 4B Glitch?

Let's call this The 4B Glitch, or any situation where a computer is being asked to store a number greater than 4294967294, or 2^32, or roughly four billion, and fails to.

In these situations a very large number can look to the computer like a very small number. Computer engineers call these "boundary conditions", and this is often where software fails. When you design a system you always know that *some* data will make your software fail. In the 1950s, engineers thought 2000 was too far away to worry about. And a company with over 4 billion shares must have been unthinkable to some people who wrote trading software. The key to good system management is to know what assumptions you've made and stay conscious as the world changes and renders your assumptions invalid.

There was a lot of talk that the Dow crossing 10000 would be one such event. Apparently it wasn't a big problem. But at the same time, MSFT crossed another boundary (Murphy strikes!), and on this one, the trading systems may not have handled it gracefully. The problem may be compounded because Microsoft is part of the Standard & Poor 500, so computers that miscalculate Microsoft's numbers may also have miscalculated the S&P numbers.

A couple of examples Permalink to A couple of examples

The split was announced two months ago, and my friend, who is a software developer, wondered if the computer trading systems would work.

On Monday he watched the websites of the major stock services, and based on what he saw, he believes that they weren't handling the change. Quote.Com, Schwab, MSN, even the Nasdaq site, all had serious errors, in billions of dollars of missing shareholder value, and some of them still have the errors as I write this on Tuesday morning, three days after the stock split.

Last night if you went to www.nasdaq.com, you'd have seen grossly incorrect numbers for the number of outstanding MSFT shares, for market capitalization and for P/E Ratio. They will of course eventually fix this, so I took a screen shot.

The numbers are incorrect by a factor of two. They have Microsoft's market cap at half what it should be and its P/E ratio also at half the correct amount.

And this morning, Quote.Com also has the incorrect off-by-a-power-of-two value for MSFT's P/E ratio.

Now I don't know if the errors are due to the 4B Glitch, I've checked with people who understand trading software, and I am told that software generally records the number of thousands of shares, not the actual number of shares. But right now the web isn't doing a good job with the value of MSFT. Is this unusual? Please let me know.

Dave Winer Permalink to Dave Winer

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