Again, I disagree. I think most people will understand it in the way I said above, because for most people, "invest" does not imply "bought shares of." Because of your involvement in the startup community, you tend to assume a specialized definition of "invest" rather than the general definition that most people assume.
99 times out of 100 (at least) on Hacker News, "invest" connotes an actual ownership share.
Which is related to what I said about being plugged into the startup community. This article, however, appeared in Wired, which is a more general magazine.