Abstract
Freedom to operate (FTO) is a central precondition for appropriating profits from own-used inventions. One way to secure FTO is defensive publishing, that is, the publication of inventions with the purpose of creating prior art. Prior research has shown that firms use also the patent system for defensive publishing, but a quantitative analysis of this practice is lacking. We address this gap by identifying defensive publications among applications at the German patent office. Based on an analysis of all direct first filings between 1986 and 2000, we find that more than 5% of them could turn out to have defensive publishing as their sole purpose. This finding gives an indication that, for all other applications, the share of their value attributable to creating FTO might be considerable. We further find that 20% of all applications are left pending for the maximum of seven years before examination is requested or the application is deemed to be withdrawn, revealing the value of even a pending application.