Many Cards Versus One Card and a List Field

[J. Downs]

> What made it possible to use HC that way was its "hint bits", a  
> system for indexing field contents which is not only proprietary  
> but patented as well.  Hint bits made it ultra-fast for obtaining  
> data across the otherwise-complex structures that make up cards and  
> fields.

Certainly any such patent has expired by now.  Patents are  
enforceable a maximum of 20 years past the filing date.

J.