One strategy they use is creating so-called " patent thickets" around existing products.
他们使用的一种策略是在现有产品周围创建所谓的“专利丛林”。
英语百科
Patent thicket
（重定向自Patent thickets）
A patent thicket carries a negative connotation and is best described as "a dense web of overlapping intellectual property rights that a company must hack its way through in order to actually commercialize new technology," or, in other words, "an overlapping set of patent rights” which requires innovators to reach licensing deals for multiple patents from multiple sources."