耐嚼的一段话。

“If national patent laws did not exist, it would be difficult to make a conclusive case for introducing them; but the fact that they do exist shifts the burden of proof and it is equally difficult to make a really conclusive case for abolishing them.”  Penrose (1951)

如果国家专利法不存在，做出引进它们的决定将非常困难；但是如果事实是它们存在并且分担了提供证据的责任，那么如果要确实做出废除它们的决定也同样困难。

关键是没有上下文，conclusive 是决定性的，但是case不知道代指什么。所以把conclusive case 译为决定。
Intellectual Property  Right 我也不懂。

nice ,thanks.

不客气 呵呵，仅供参考啦。

but the fact that they do exist shifts the burden of proof

啰嗦一下，这句中fact 是主语，that 引导一个定语从句修饰fact，shifts 是谓语。

所以事实上是：它们确实存在的事实分担了提供证据的责任。

呵呵。