金融衍生品

以下内容不要轻易看，确实不容易懂，尤其是不要以为自己懂了就去做，尤其尤其不要用option去做投机！金融衍生品有很多种，option是其中的一种。可以基于各种目的使用金融衍生品。比如：保险、对冲、投机、投资etc。。。。巴菲特卖的S&P的put option实际上就是一种（长线）投资，由于他用…

Source: http://nteswjq.blog.163.com/blog/static/1269981201071045536949/

Financial derivatives

> By Duan Yongping · his NetEase blog (nteswjq.blog.163.com, now closed; read from web archives) · 2010-08-10 · [Original link](http://nteswjq.blog.163.com/blog/static/1269981201071045536949/) ([archived](https://web.archive.org/web/20110720170753/http://nteswjq.blog.163.com/blog/static/1269981201071045536949/))

Don't read what follows lightly; it's really not easy to understand. Above all, don't think you understand and go do it, and above all above all, don't use options to speculate!

There are many kinds of financial derivatives; options are one of them.

Financial derivatives can be used for all kinds of purposes. For example: insurance, hedging, speculation, investment, etc....

The S&P put options Buffett sold are actually a kind of (long-term) investment. Because he uses his credit as the guarantee, and they can only be exercised on the expiry date, I don't think he's using margin.

Ordinary people like us can't do the same trade. We must have collateral, and they can be exercised at any time. When our collateral isn't cash, it's effectively the same as using margin.

I also sold (look carefully: sold! Lots of people read this and go buy, very confusing) some SPY puts.

I'm listing them for anyone interested to take a look, to see whether it helps.

[Translator's note: the trade records below are Duan Yongping's own order slip, kept as in the original (English in the original); they are not counted in the ratio.]

```
05/25/2010
Sell to Open200
SPY 03/19/2011 100.00 P
PUT SPDR S&P 500 ETF TR$100 EXP 03/19/11
$10.09

05/25/2010
Sell to Open200
SPY 09/18/2010 100.00 P
PUT SPDR S&P 500 ETF TR$100 EXP 09/18/10$5.86

05/25/2010
Sell to Open200
SPY 12/18/2010 100.00 P
PUT SPDR S&P 500 ETF TR$100 ADJ EXP 12/18/10$8.24

05/25/2010
Sell to Open200
SPY 08/21/2010 100.00 P
PUT SPDR S&P 500 ETF TR$100 EXP 08/21/10$4.96

05/25/2010
Sell to Open200
SPY 07/17/2010 105.00 P
PUT SPDR S&P 500 ETF TR$105 EXP 07/17/10$5.31

05/25/2010
Sell to Open200
SPY 06/19/2010 105.00 P
PUT SPDR S&P 500 ETF TR$105 EXP 06/19/10$3.82
```

Above are the S&P ETF puts I sold on May 25: 1,200 contracts in total, equivalent to 120,000 shares. (I removed the commission column.)

Some have already expired, some expire this month, and some have a long time before they expire. In total I collected over 760,000; for the unexpired ones I don't know yet whether they'll lose or win.

The profit isn't high, but the risk is also very small.

I think that selling puts for me is a bit like Buffett's arbitrage: when there are no obviously good targets, using the money in hand to earn some interest.

Those who don't trade US stocks, please skip this post.