Barry Schwartz, Search Engine Land – “Google Search has added to its file types indexable by Google help document that it can now index Comma-Separated Values (.csv) files. I confirmed with John Mueller of Google that this is not just a help document update but a new update to Google Search in what it can index. More details. I spotted the update this morning to the help document and wondered initially if this is new outside of just an update to a help document for clarification purposes. I reached out to John Mueller who confirmed with me on Twitter that this is newly added functionally to Google Search:

Why we care. If you have CSV files out on the web, Google can now index those files. That means that Google Search can show CSV files in its search results when relevant to the query. If you don’t want your CSV files in Google Search, make sure you don’t let Google index them.”