[saulrh]

Some articles I've read suggest that it's intentional on the part of the applicant. The idea is to extend the useful life of the patent by delaying the application's completion as much as possible.

[pat2man]

Definitely worked well for some people:

"By April 1988, when Gould's use patent was approved, optically pumped amplifier patents covered 80% of the lasers made in the United States. The market for lasers had ballooned to more than $500 million per year. Suddenly, Gould was a multimillionaire."

http://electronicdesign.com/article/components/gordon-gould-...

[anamax]

> The idea is to extend the useful life of the patent by delaying the application's completion as much as possible.

That hasn't worked for around 20 years - the "if issued term" clock starts ticking the day that you apply.

This is a huge problem for drug companies because their applications take a long time to issue.