The date of a "patented"

The date of a "patented"，是指已公告且能夠執行專利權的日子。

The date of a "patented" event under 102(a) and 102(b)
is the fate that the patent rights become enforceable,
i.e., the date the sovereign formally bestows patent rights to the applicant,
if the patent document is accessible to the public when granted.

小小的改善，亦具有進步性。

在一個高度發展的技術領域，一個小小的改善，亦具有進步性。

http://www.tms.org/pubs/journals/jom/matters/matters-9609.html
Crowded Art: This refers to an area of technology in which there have been a large number of prior inventions. In a crowded art, it takes less of an advancement to obtain a valid patent. Otherwise, one would have to conclude that there can be no further patenting in that art.

http://www.dallasbar.com/members/headnotes_showarticle.asp?article_id=1447&issue_id=131
For example, in Gemtron Corp. v. Saint-Gobain Corp., the District Court for the Western District of Michigan denied summary judgment and found that “KSR does not automatically call for a ruling of invalidity unless the patent challenged is a major development in the art” because even “narrow improvements in a crowded art” continue to be patentable.