...depending on the technology that's being patented, it can take anywhere from two to five years for a patent to issue. As far as costs, expect to spend anywhere from $10,000 to as high as $30,000 for highly complex technologies. Patentability searches account for up to a thousand of that, application fees can add up to another couple thousand, and the rest is attorney fees for patentability opinions, initial patent drafting, and [Patent and Trademark Office] action responses and appeals.Given that about 1/3 of patent applications is granted and only 5% of patents are worth something, the "retail" price of a decent portfolio (20+ patents) runs from $600K to $1.8M. This means that for most startups, unless a comprehensive invention and patent strategy is in place, filing patent applications is a crapshoot at best.
It is also a good indicator of the existence of an underserved market.