I was recently at a "tech" conference that focused on entrepreneurs, and I watched a panel discussion on "legal issues" where the first speaker went on at length about why startups absolutely needed
to apply for patents as soon as possible. He argued that so much of a company's value was "tied up" in its "intellectual property" and you absolutely needed to "protect" it or the company could just be copied. This shows a fundamental misunderstanding of true value. The idea, by itself, is somewhat meaningless. The real issue is the execution -- and no matter what you know about the idea, the actual execution is always a lot more difficult. Focusing on "protecting" rather than executing can actually be the death of a startup.
Thankfully, it looks like more and more startups in the "soft technology" realm are recognizing this, and are getting fewer and fewer patents. TechCrunch has a post by patent lawyer Leonid Kravets who did a study of patents and funded companies, and found that each year over the past few years, startups seem to be getting fewer patents
It may be tough to tell from the chart, but basically, each year shows fewer patent applications from startups. There's a ton of other interesting data at the link above, including some differences between certain investors. Not surprisingly, corporate VC wings seem to like companies with patents (a very big company mentality). Whereas VCs that have been investing in some of the most successful startups today (like Accel, which funded Facebook, and Union Square, which funded Twitter, Kickstarter, FourSquare, Tumblr and many others) have a much lower number of startups they invest in that have patents. Those VCs seem to recognize that it's not the patents that matter, and the general success of both of those firms' portfolios suggests they may be on to something.