I used `dull patent` as a synonym of `stupid patent`[1], so you are right with the meaning you inferred.<p>[1] <a href="https:&#x2F;&#x2F;www.eff.org&#x2F;issues&#x2F;stupid-patent-month" rel="nofollow">https:&#x2F;&#x2F;www.eff.org&#x2F;issues&#x2F;stupid-patent-month</a>