[Plugin: AddThis] [Plugin: JSON API] Special characters added to excerpt

Our website loads several sections of its home page via Javascript from the JSON API. It does this for performance reasons, but lately we noticed a strange set of characters appearing: +-* before some of the content. After doing some digging, it appears that these characters are added by the AddThis plugin, in order to load some of that plugin’s tooling.

Unfortunately, because our site is loading content from the API, it is appearing on the page after AddThis has already swept the markup for those characters – meaning they stay visible.

We discovered this problem on a private testing server, so there isn’t a public URL I can share that exhibits this problem. I’ve verified that the characters are in the JSON markup by loading that directly. If needed, I can try and set up a small public server that exhibits this behavior – but it may take some doing to replicate our setup. You can see our existing public front page at http://libraries.mit.edu – the affected sections are the four headshots of experts, more than halfway down the right column. Their areas of expertise were displaying as +-*BIOSCIENCES for example, instead of BIOSCIENCES.

I’m not sure where the needed solution to this problem lies. Is it a problem with the JSON API that these characters are being added to its output? Is it a problem with AddThis that they are augmenting the excerpt in _all_ cases, rather than just HTML responses?

Any guidance on this question would be appreciated.