The query does not return the values ​​for NULL

I am having a bit of trouble with a query for SQL Server 2008.

I have a table with some values and a category. This category can be e.g. Stock, Bond or NULL.

Then I may want to see everything in my table that is not bonds:

SELECT Value, Name, Currency, Assetclass
FROM MyTable
WHERE Assetclass <> 'Bond'

Here I expect to see all my assets that are Stock and uncategorised (NULL). But instead I only see the stocks. I get the same result as setting my Where-condition to Assetclass = 'Stock'.

I am aware that NULL is treated as an unidentified value, but I would expect it to only disregard rows that contain exactly 'Bond' and keep everything else, but this is apparently not the case?

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As others have pointed out, this is the expected behavior. If you don't want to do an ORyou could always replace null with something else in your comparison:

WHERE ISNULL(Assetclass, 'Anything but Bond') <> 'Bond'