网上有很多传言；唯一的官方说明，是国务院官网 2012 年签证问答 webchat 的记录：
Q: [...] There is a star or * symbol below the bottom left of my photo, does that signify anything?
A: The star symbol is not of any significance.
Wow, you have a keen eye! [smiley] Those are computer-generated features that help make each visa as unique as the people who obtain them. [smiley]
另外参见 Quora 上的这个回答：
As far as I know (and I know a lot about visas), it means absolutely nothing.
There's a rumor going around that refuses to die that stars have something to do with "risk factor". Bullshit. Bull. Shit.
We don't give visas to high-risk individuals, and if we did we certainly wouldn't put anything obvious on a visa to let you know we're onto you.